diff --git a/main/src/com/google/refine/expr/functions/arrays/Join.java b/main/src/com/google/refine/expr/functions/arrays/Join.java
index 64b571d32..492ab9448 100644
--- a/main/src/com/google/refine/expr/functions/arrays/Join.java
+++ b/main/src/com/google/refine/expr/functions/arrays/Join.java
@@ -41,6 +41,7 @@ import org.json.JSONException;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.ExpressionUtils;
+import com.google.refine.expr.util.JsonValueConverter;
 import com.google.refine.grel.ControlFunctionRegistry;
 import com.google.refine.grel.Function;
 
@@ -75,7 +76,7 @@ public class Join implements Function {
                                 sb.append(separator);
                             }
                             try {
-                                sb.append(a.get(i).toString());
+                                sb.append(JsonValueConverter.convert(a.get(i)).toString());
                             } catch (JSONException e) {
                                 return new EvalError(ControlFunctionRegistry.getFunctionName(this) + 
                                     " cannot retrieve element " + i + " of array");
diff --git a/main/tests/server/src/com/google/refine/tests/grel/GrelTests.java b/main/tests/server/src/com/google/refine/tests/grel/GrelTests.java
index e52dc1b90..9cb69544c 100644
--- a/main/tests/server/src/com/google/refine/tests/grel/GrelTests.java
+++ b/main/tests/server/src/com/google/refine/tests/grel/GrelTests.java
@@ -179,6 +179,12 @@ public class GrelTests extends RefineTest {
         Evaluable eval = MetaParser.parse("grel:" + test);
         Assert.assertNull(eval.evaluate(bindings));
     }
+    
+    @Test
+    public void testJoinJsonArray() throws ParsingException {
+        String test[] = { "\"{\\\"values\\\":[\\\"one\\\",\\\"two\\\",\\\"three\\\"]}\".parseJson().values.join(\",\")", "one,two,three" };
+        parseEval(bindings, test);
+    }
 
     @Test
     public void testGetFieldFromNull() throws ParsingException {