diff --git a/src/runtime/runtime.cs b/src/runtime/runtime.cs
index b08a56622..b4ddc7f7e 100644
--- a/src/runtime/runtime.cs
+++ b/src/runtime/runtime.cs
@@ -1190,7 +1190,11 @@ internal static bool PyString_Check(IntPtr ob)
 
         internal static IntPtr PyString_FromString(string value)
         {
+#if PYTHON3
+            return PyUnicode_FromKindAndData(_UCS, value, value.Length);
+#elif PYTHON2
             return PyString_FromStringAndSize(value, value.Length);
+#endif
         }
 
 #if PYTHON3
@@ -1205,13 +1209,6 @@ internal static IntPtr PyBytes_AS_STRING(IntPtr ob)
             return ob + BytesOffset.ob_sval;
         }
 
-        [DllImport(_PythonDll, CallingConvention = CallingConvention.Cdecl,
-            EntryPoint = "PyUnicode_FromStringAndSize")]
-        internal static extern IntPtr PyString_FromStringAndSize(
-            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalTypeRef = typeof(Utf8Marshaler))] string value,
-            int size
-        );
-
         [DllImport(_PythonDll, CallingConvention = CallingConvention.Cdecl)]
         internal static extern IntPtr PyUnicode_FromStringAndSize(IntPtr value, int size);
 #elif PYTHON2
diff --git a/src/testing/conversiontest.cs b/src/testing/conversiontest.cs
index 36294594c..06ab7cb4e 100644
--- a/src/testing/conversiontest.cs
+++ b/src/testing/conversiontest.cs
@@ -60,4 +60,19 @@ public string GetValue()
             return value;
         }
     }
+    
+    public class UnicodeString
+    {
+        public string value = "안녕";
+
+        public string GetString()
+        {
+            return value;
+        }
+
+        public override string ToString()
+        {
+            return value;
+        }
+    }
 }
diff --git a/src/tests/test_conversion.py b/src/tests/test_conversion.py
index 53e5d8051..0ba10a80e 100644
--- a/src/tests/test_conversion.py
+++ b/src/tests/test_conversion.py
@@ -2,11 +2,12 @@
 
 """Test CLR <-> Python type conversions."""
 
+from __future__ import unicode_literals
 import System
 import pytest
-from Python.Test import ConversionTest
+from Python.Test import ConversionTest, UnicodeString
 
-from ._compat import indexbytes, long, unichr
+from ._compat import indexbytes, long, unichr, text_type, PY2, PY3
 
 
 def test_bool_conversion():
@@ -535,6 +536,14 @@ def test_string_conversion():
 
     with pytest.raises(TypeError):
         ConversionTest().StringField = 1
+    
+    world = UnicodeString()
+    test_unicode_str = u"안녕"
+    assert test_unicode_str == text_type(world.value)
+    assert test_unicode_str == text_type(world.GetString())
+    # TODO: not sure what to do for Python 2 here (GH PR #670)
+    if PY3:
+        assert test_unicode_str == text_type(world)
 
 
 def test_interface_conversion():