diff --git a/jsonpb/jsonpb.go b/jsonpb/jsonpb.go
index f4523f5..d1f6f28 100644
--- a/jsonpb/jsonpb.go
+++ b/jsonpb/jsonpb.go
@@ -107,6 +107,12 @@
 	}
 	if wkt, ok := v.(wkt); ok {
 		switch wkt.XXX_WellKnownType() {
+		case "DoubleValue", "FloatValue", "Int64Value", "UInt64Value",
+			"Int32Value", "UInt32Value", "BoolValue", "StringValue", "BytesValue":
+			// "Wrappers use the same representation in JSON
+			//  as the wrapped primitive type, ..."
+			sprop := proto.GetProperties(s.Type())
+			return m.marshalValue(out, sprop.Prop[0], s.Field(0), indent)
 		case "Duration":
 			// "Generated output always contains 3, 6, or 9 fractional digits,
 			//  depending on required precision."
@@ -427,6 +433,13 @@
 	}
 	if wkt, ok := target.Addr().Interface().(wkt); ok {
 		switch wkt.XXX_WellKnownType() {
+		case "DoubleValue", "FloatValue", "Int64Value", "UInt64Value",
+			"Int32Value", "UInt32Value", "BoolValue", "StringValue", "BytesValue":
+			// "Wrappers use the same representation in JSON
+			//  as the wrapped primitive type, except that null is allowed."
+			// encoding/json will turn JSON `null` into Go `nil`,
+			// so we don't have to do any extra work.
+			return unmarshalValue(target.Field(0), inputValue)
 		case "Duration":
 			unq, err := strconv.Unquote(string(inputValue))
 			if err != nil {
diff --git a/jsonpb/jsonpb_test.go b/jsonpb/jsonpb_test.go
index f5612b9..a970063 100644
--- a/jsonpb/jsonpb_test.go
+++ b/jsonpb/jsonpb_test.go
@@ -41,6 +41,7 @@
 	proto3pb "github.com/golang/protobuf/proto/proto3_proto"
 	durpb "github.com/golang/protobuf/ptypes/duration"
 	tspb "github.com/golang/protobuf/ptypes/timestamp"
+	wpb "github.com/golang/protobuf/ptypes/wrappers"
 )
 
 var (
@@ -321,6 +322,16 @@
 
 	{"Duration", marshaler, &pb.KnownTypes{Dur: &durpb.Duration{Seconds: 3}}, `{"dur":"3.000s"}`},
 	{"Timestamp", marshaler, &pb.KnownTypes{Ts: &tspb.Timestamp{Seconds: 14e8, Nanos: 21e6}}, `{"ts":"2014-05-13T16:53:20.021Z"}`},
+
+	{"DoubleValue", marshaler, &pb.KnownTypes{Dbl: &wpb.DoubleValue{Value: 1.2}}, `{"dbl":1.2}`},
+	{"FloatValue", marshaler, &pb.KnownTypes{Flt: &wpb.FloatValue{Value: 1.2}}, `{"flt":1.2}`},
+	{"Int64Value", marshaler, &pb.KnownTypes{I64: &wpb.Int64Value{Value: -3}}, `{"i64":"-3"}`},
+	{"UInt64Value", marshaler, &pb.KnownTypes{U64: &wpb.UInt64Value{Value: 3}}, `{"u64":"3"}`},
+	{"Int32Value", marshaler, &pb.KnownTypes{I32: &wpb.Int32Value{Value: -4}}, `{"i32":-4}`},
+	{"UInt32Value", marshaler, &pb.KnownTypes{U32: &wpb.UInt32Value{Value: 4}}, `{"u32":4}`},
+	{"BoolValue", marshaler, &pb.KnownTypes{Bool: &wpb.BoolValue{Value: true}}, `{"bool":true}`},
+	{"StringValue", marshaler, &pb.KnownTypes{Str: &wpb.StringValue{Value: "plush"}}, `{"str":"plush"}`},
+	{"BytesValue", marshaler, &pb.KnownTypes{Bytes: &wpb.BytesValue{Value: []byte("wow")}}, `{"bytes":"d293"}`},
 }
 
 func TestMarshaling(t *testing.T) {
@@ -363,6 +374,18 @@
 
 	{"Duration", `{"dur":"3.000s"}`, &pb.KnownTypes{Dur: &durpb.Duration{Seconds: 3}}},
 	{"Timestamp", `{"ts":"2014-05-13T16:53:20.021Z"}`, &pb.KnownTypes{Ts: &tspb.Timestamp{Seconds: 14e8, Nanos: 21e6}}},
+
+	{"DoubleValue", `{"dbl":1.2}`, &pb.KnownTypes{Dbl: &wpb.DoubleValue{Value: 1.2}}},
+	{"FloatValue", `{"flt":1.2}`, &pb.KnownTypes{Flt: &wpb.FloatValue{Value: 1.2}}},
+	{"Int64Value", `{"i64":"-3"}`, &pb.KnownTypes{I64: &wpb.Int64Value{Value: -3}}},
+	{"UInt64Value", `{"u64":"3"}`, &pb.KnownTypes{U64: &wpb.UInt64Value{Value: 3}}},
+	{"Int32Value", `{"i32":-4}`, &pb.KnownTypes{I32: &wpb.Int32Value{Value: -4}}},
+	{"UInt32Value", `{"u32":4}`, &pb.KnownTypes{U32: &wpb.UInt32Value{Value: 4}}},
+	{"BoolValue", `{"bool":true}`, &pb.KnownTypes{Bool: &wpb.BoolValue{Value: true}}},
+	{"StringValue", `{"str":"plush"}`, &pb.KnownTypes{Str: &wpb.StringValue{Value: "plush"}}},
+	{"BytesValue", `{"bytes":"d293"}`, &pb.KnownTypes{Bytes: &wpb.BytesValue{Value: []byte("wow")}}},
+	// `null` is also a permissible value. Let's just test one.
+	{"null DoubleValue", `{"dbl":null}`, &pb.KnownTypes{Dbl: &wpb.DoubleValue{}}},
 }
 
 func TestUnmarshaling(t *testing.T) {
diff --git a/jsonpb/jsonpb_test_proto/Makefile b/jsonpb/jsonpb_test_proto/Makefile
index d16e916..d6e9768 100644
--- a/jsonpb/jsonpb_test_proto/Makefile
+++ b/jsonpb/jsonpb_test_proto/Makefile
@@ -30,4 +30,4 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 regenerate:
-	protoc --go_out=Mgoogle/protobuf/duration.proto=github.com/golang/protobuf/ptypes/duration,Mgoogle/protobuf/timestamp.proto=github.com/golang/protobuf/ptypes/timestamp:. *.proto
+	protoc --go_out=Mgoogle/protobuf/duration.proto=github.com/golang/protobuf/ptypes/duration,Mgoogle/protobuf/timestamp.proto=github.com/golang/protobuf/ptypes/timestamp,Mgoogle/protobuf/wrappers.proto=github.com/golang/protobuf/ptypes/wrappers:. *.proto
diff --git a/jsonpb/jsonpb_test_proto/test_objects.pb.go b/jsonpb/jsonpb_test_proto/test_objects.pb.go
index cf6f0e3..de58e89 100644
--- a/jsonpb/jsonpb_test_proto/test_objects.pb.go
+++ b/jsonpb/jsonpb_test_proto/test_objects.pb.go
@@ -9,6 +9,7 @@
 import math "math"
 import google_protobuf "github.com/golang/protobuf/ptypes/duration"
 import google_protobuf1 "github.com/golang/protobuf/ptypes/timestamp"
+import google_protobuf2 "github.com/golang/protobuf/ptypes/wrappers"
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -517,9 +518,18 @@
 }
 
 type KnownTypes struct {
-	Dur              *google_protobuf.Duration   `protobuf:"bytes,1,opt,name=dur" json:"dur,omitempty"`
-	Ts               *google_protobuf1.Timestamp `protobuf:"bytes,2,opt,name=ts" json:"ts,omitempty"`
-	XXX_unrecognized []byte                      `json:"-"`
+	Dur              *google_protobuf.Duration     `protobuf:"bytes,1,opt,name=dur" json:"dur,omitempty"`
+	Ts               *google_protobuf1.Timestamp   `protobuf:"bytes,2,opt,name=ts" json:"ts,omitempty"`
+	Dbl              *google_protobuf2.DoubleValue `protobuf:"bytes,3,opt,name=dbl" json:"dbl,omitempty"`
+	Flt              *google_protobuf2.FloatValue  `protobuf:"bytes,4,opt,name=flt" json:"flt,omitempty"`
+	I64              *google_protobuf2.Int64Value  `protobuf:"bytes,5,opt,name=i64" json:"i64,omitempty"`
+	U64              *google_protobuf2.UInt64Value `protobuf:"bytes,6,opt,name=u64" json:"u64,omitempty"`
+	I32              *google_protobuf2.Int32Value  `protobuf:"bytes,7,opt,name=i32" json:"i32,omitempty"`
+	U32              *google_protobuf2.UInt32Value `protobuf:"bytes,8,opt,name=u32" json:"u32,omitempty"`
+	Bool             *google_protobuf2.BoolValue   `protobuf:"bytes,9,opt,name=bool" json:"bool,omitempty"`
+	Str              *google_protobuf2.StringValue `protobuf:"bytes,10,opt,name=str" json:"str,omitempty"`
+	Bytes            *google_protobuf2.BytesValue  `protobuf:"bytes,11,opt,name=bytes" json:"bytes,omitempty"`
+	XXX_unrecognized []byte                        `json:"-"`
 }
 
 func (m *KnownTypes) Reset()                    { *m = KnownTypes{} }
@@ -541,6 +551,69 @@
 	return nil
 }
 
+func (m *KnownTypes) GetDbl() *google_protobuf2.DoubleValue {
+	if m != nil {
+		return m.Dbl
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetFlt() *google_protobuf2.FloatValue {
+	if m != nil {
+		return m.Flt
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetI64() *google_protobuf2.Int64Value {
+	if m != nil {
+		return m.I64
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetU64() *google_protobuf2.UInt64Value {
+	if m != nil {
+		return m.U64
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetI32() *google_protobuf2.Int32Value {
+	if m != nil {
+		return m.I32
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetU32() *google_protobuf2.UInt32Value {
+	if m != nil {
+		return m.U32
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetBool() *google_protobuf2.BoolValue {
+	if m != nil {
+		return m.Bool
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetStr() *google_protobuf2.StringValue {
+	if m != nil {
+		return m.Str
+	}
+	return nil
+}
+
+func (m *KnownTypes) GetBytes() *google_protobuf2.BytesValue {
+	if m != nil {
+		return m.Bytes
+	}
+	return nil
+}
+
 var E_Name = &proto.ExtensionDesc{
 	ExtendedType:  (*Real)(nil),
 	ExtensionType: (*string)(nil),
@@ -564,56 +637,65 @@
 }
 
 var fileDescriptor1 = []byte{
-	// 812 bytes of a gzipped FileDescriptorProto
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-	0x00, 0x00, 0xff, 0xff, 0x73, 0x4f, 0x6f, 0xec, 0x73, 0x06, 0x00, 0x00,
+	// 947 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0x7c, 0x95, 0xd1, 0x72, 0xdb, 0x44,
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+	0x54, 0x75, 0xa0, 0x18, 0x81, 0x02, 0x0b, 0x0a, 0x3a, 0x50, 0x8c, 0x40, 0x41, 0x07, 0x0a, 0x2c,
+	0x28, 0x46, 0xa0, 0xc0, 0x82, 0x02, 0x0b, 0x8a, 0x11, 0x28, 0xb0, 0xa0, 0xa0, 0x03, 0xc5, 0x08,
+	0x14, 0x18, 0x50, 0xff, 0x62, 0x43, 0x3d, 0x4f, 0xcf, 0x96, 0x49, 0x2d, 0xee, 0x72, 0xf7, 0x85,
+	0xca, 0x14, 0xe8, 0x7e, 0xda, 0x9f, 0x1e, 0x44, 0xa6, 0xa9, 0x23, 0x23, 0x47, 0x8f, 0x49, 0x93,
+	0xc6, 0x22, 0x3e, 0xa3, 0x3c, 0xe3, 0x26, 0x78, 0xbb, 0xdc, 0x03, 0xd0, 0xff, 0xc5, 0x1d, 0x3e,
+	0xa8, 0x74, 0xd7, 0xea, 0x03, 0x1c, 0x4e, 0xf7, 0x5b, 0xb7, 0xe9, 0x65, 0xd9, 0xa8, 0xe2, 0x63,
+	0x03, 0x44, 0x3b, 0x69, 0x9f, 0xdb, 0x4e, 0x02, 0xd4, 0x58, 0x3d, 0x30, 0x07, 0x1c, 0x1e, 0xe8,
+	0xcc, 0x37, 0x5a, 0x67, 0x73, 0xee, 0xb2, 0xd5, 0xc5, 0xa7, 0x3c, 0x80, 0x79, 0x6b, 0xbe, 0xa1,
+	0x63, 0xb7, 0xcc, 0x3e, 0x34, 0xbf, 0x26, 0x1f, 0x72, 0xd7, 0x6c, 0xda, 0xe3, 0x4c, 0xce, 0x8e,
+	0x46, 0xd7, 0x44, 0xc0, 0xdd, 0x6f, 0xe5, 0x6c, 0xf6, 0x74, 0xd4, 0x13, 0x3e, 0xef, 0x1f, 0xfe,
+	0x70, 0x3a, 0x1b, 0x39, 0x93, 0x3f, 0x1d, 0xde, 0x3f, 0x8e, 0xcb, 0x4a, 0x7c, 0xc9, 0x87, 0xb9,
+	0x69, 0x17, 0x62, 0xaf, 0x7b, 0x6c, 0x38, 0x7d, 0xa7, 0xcd, 0x27, 0x4b, 0x74, 0xac, 0xfb, 0x07,
+	0x8f, 0x62, 0x56, 0xd4, 0xb0, 0x96, 0x41, 0xde, 0xae, 0xc5, 0xd7, 0x7c, 0x2f, 0xd7, 0xbd, 0xd9,
+	0x3e, 0xb5, 0xa3, 0xcb, 0xdf, 0xbd, 0x5c, 0x4e, 0xfd, 0x6a, 0x1e, 0xdb, 0x04, 0x0c, 0x73, 0x7b,
+	0x65, 0xfc, 0x15, 0xdf, 0xbf, 0x9c, 0x2f, 0x46, 0x9c, 0xfd, 0x92, 0xac, 0xf5, 0x31, 0x32, 0x49,
+	0x3f, 0xc5, 0x01, 0x77, 0x7f, 0x8d, 0xb3, 0x55, 0xa2, 0x47, 0x42, 0x20, 0xcd, 0xe2, 0x91, 0xf3,
+	0x45, 0x6f, 0xfc, 0x94, 0x8f, 0xae, 0xc6, 0x6f, 0xd6, 0xfb, 0xa6, 0xfe, 0x83, 0xcd, 0xfa, 0xed,
+	0x43, 0xb1, 0x79, 0x93, 0x27, 0xfc, 0xfa, 0x71, 0xb5, 0x7c, 0x9e, 0xd6, 0x3f, 0xff, 0x58, 0x24,
+	0xea, 0x5c, 0xbc, 0xc5, 0xdd, 0x3a, 0xad, 0xf1, 0xc1, 0x28, 0x2d, 0xf8, 0xee, 0x9a, 0x34, 0x4b,
+	0x11, 0x62, 0x47, 0xc4, 0x59, 0x0c, 0x6b, 0x1d, 0xc9, 0x50, 0x68, 0xd6, 0x87, 0x1e, 0x77, 0x57,
+	0x05, 0x8e, 0xcc, 0xc9, 0x1d, 0xde, 0x97, 0x49, 0x9c, 0xd9, 0xcd, 0xf7, 0xf4, 0x5c, 0x30, 0x8b,
+	0xbb, 0xbe, 0x7f, 0x36, 0xfa, 0x03, 0xff, 0x9c, 0xc9, 0x05, 0xf7, 0x1e, 0x2b, 0xda, 0xc7, 0x2b,
+	0x71, 0x8b, 0x07, 0x69, 0x1e, 0x2f, 0xd3, 0x82, 0x82, 0x8d, 0xdd, 0x5e, 0xb0, 0x25, 0xd3, 0x23,
+	0xbe, 0x0f, 0x18, 0x3d, 0x4f, 0x5e, 0xd5, 0x49, 0x51, 0xe1, 0xcd, 0xc4, 0x75, 0xdb, 0x10, 0x71,
+	0x16, 0xfe, 0x76, 0xb9, 0xa3, 0x9a, 0x78, 0xb9, 0x47, 0x45, 0xb3, 0xb6, 0x66, 0xf2, 0x57, 0x9f,
+	0xf3, 0xef, 0x0b, 0x75, 0x51, 0x3c, 0x5b, 0x97, 0x49, 0x25, 0x3e, 0xe1, 0x0c, 0xc7, 0xbd, 0xbe,
+	0xed, 0x70, 0x7a, 0x33, 0x32, 0x93, 0x3c, 0x6a, 0x27, 0x79, 0x74, 0xd4, 0x7c, 0x0a, 0x24, 0xb9,
+	0xf0, 0x65, 0x73, 0xb0, 0x19, 0x0d, 0xce, 0xf1, 0x96, 0xf7, 0x59, 0xfb, 0x59, 0x90, 0xe8, 0x12,
+	0x11, 0x06, 0x2f, 0x32, 0x3d, 0xb5, 0x87, 0xd3, 0x5b, 0xdb, 0xc1, 0xfa, 0xed, 0xff, 0x89, 0xa8,
+	0x48, 0x32, 0xe2, 0xcb, 0xc9, 0xce, 0xb3, 0x5a, 0xcf, 0x72, 0xea, 0xc4, 0xab, 0x7e, 0x3d, 0x47,
+	0x1a, 0x3b, 0xfa, 0xc8, 0x9e, 0x36, 0xf3, 0xfd, 0x75, 0x76, 0xdd, 0x5b, 0x8d, 0x1d, 0x7d, 0xb4,
+	0x9b, 0x15, 0xda, 0x07, 0x3b, 0x76, 0x73, 0xba, 0xe9, 0x47, 0xa3, 0x8e, 0xc7, 0xd1, 0xe7, 0xed,
+	0x8e, 0xbf, 0x3f, 0x6d, 0xe3, 0x71, 0x26, 0x52, 0x3c, 0xda, 0xfd, 0xff, 0x89, 0xef, 0xfc, 0x2b,
+	0xed, 0xef, 0xeb, 0xd9, 0x1e, 0xec, 0x40, 0x49, 0xcd, 0x6d, 0xec, 0xda, 0x47, 0xf9, 0xf4, 0x9a,
+	0xf2, 0x1d, 0xf9, 0x66, 0x5e, 0x36, 0xf9, 0x68, 0x14, 0x9f, 0x73, 0xd7, 0x7e, 0x60, 0x5e, 0xf7,
+	0x00, 0x7a, 0x8e, 0x9a, 0x02, 0xe3, 0x7c, 0x74, 0x9b, 0xf7, 0x8b, 0x38, 0x4f, 0xae, 0xf4, 0xd4,
+	0xef, 0xfa, 0xd5, 0xd3, 0xca, 0x7f, 0x01, 0x00, 0x00, 0xff, 0xff, 0xa1, 0xac, 0xb6, 0x4e, 0x44,
+	0x08, 0x00, 0x00,
 }
diff --git a/jsonpb/jsonpb_test_proto/test_objects.proto b/jsonpb/jsonpb_test_proto/test_objects.proto
index 8087f71..394c424 100644
--- a/jsonpb/jsonpb_test_proto/test_objects.proto
+++ b/jsonpb/jsonpb_test_proto/test_objects.proto
@@ -33,6 +33,7 @@
 
 import "google/protobuf/duration.proto";
 import "google/protobuf/timestamp.proto";
+import "google/protobuf/wrappers.proto";
 
 package jsonpb;
 
@@ -115,4 +116,14 @@
 message KnownTypes {
   optional google.protobuf.Duration dur = 1;
   optional google.protobuf.Timestamp ts = 2;
+
+  optional google.protobuf.DoubleValue dbl = 3;
+  optional google.protobuf.FloatValue flt = 4;
+  optional google.protobuf.Int64Value i64 = 5;
+  optional google.protobuf.UInt64Value u64 = 6;
+  optional google.protobuf.Int32Value i32 = 7;
+  optional google.protobuf.UInt32Value u32 = 8;
+  optional google.protobuf.BoolValue bool = 9;
+  optional google.protobuf.StringValue str = 10;
+  optional google.protobuf.BytesValue bytes = 11;
 }