diff --git a/dataconv/marshal.go b/dataconv/marshal.go
index 3fe44e4..2c0821d 100644
--- a/dataconv/marshal.go
+++ b/dataconv/marshal.go
@@ -3,6 +3,7 @@ package dataconv
 // Based on https://github.com/qri-io/starlib/tree/master/util with some modifications and additions
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"time"
@@ -23,6 +24,8 @@ func Marshal(data interface{}) (v starlark.Value, err error) {
 		v = starlark.Bool(x)
 	case string:
 		v = starlark.String(x)
+	case json.Number:
+		v = starlark.String(x)
 	case int:
 		v = starlark.MakeInt(x)
 	case int8:
diff --git a/dataconv/marshal_test.go b/dataconv/marshal_test.go
index 28c416a..2ba7d0f 100644
--- a/dataconv/marshal_test.go
+++ b/dataconv/marshal_test.go
@@ -68,6 +68,7 @@ func TestMarshal(t *testing.T) {
 		{nil, starlark.None, ""},
 		{true, starlark.True, ""},
 		{"foo", starlark.String("foo"), ""},
+		{json.Number("42"), starlark.String("42"), ""},
 		{42, starlark.MakeInt(42), ""},
 		{int8(42), starlark.MakeInt(42), ""},
 		{int16(42), starlark.MakeInt(42), ""},