diff --git a/moshi/src/main/java/com/squareup/moshi/ClassJsonAdapter.java b/moshi/src/main/java/com/squareup/moshi/ClassJsonAdapter.java
index 691fade..7d4b5bc 100644
--- a/moshi/src/main/java/com/squareup/moshi/ClassJsonAdapter.java
+++ b/moshi/src/main/java/com/squareup/moshi/ClassJsonAdapter.java
@@ -21,6 +21,7 @@ import java.lang.annotation.Annotation;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Modifier;
+import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
 import java.util.Map;
 import java.util.Set;
@@ -46,8 +47,10 @@ final class ClassJsonAdapter<T> extends JsonAdapter<T> {
   public static final JsonAdapter.Factory FACTORY = new JsonAdapter.Factory() {
     @Override public @Nullable JsonAdapter<?> create(
         Type type, Set<? extends Annotation> annotations, Moshi moshi) {
-      if (!(type instanceof Class)) return null;
-      Class<?> rawType = (Class<?>) type;
+      if (!(type instanceof Class || type instanceof ParameterizedType)) {
+        return null;
+      }
+      Class<?> rawType = Types.getRawType(type);
       if (rawType.isInterface() || rawType.isEnum()) return null;
       if (Util.isPlatformType(rawType) && !Types.isAllowedPlatformType(rawType)) {
         throw new IllegalArgumentException("Platform "
@@ -74,7 +77,7 @@ final class ClassJsonAdapter<T> extends JsonAdapter<T> {
 
       ClassFactory<Object> classFactory = ClassFactory.get(rawType);
       Map<String, FieldBinding<?>> fields = new TreeMap<>();
-      for (Type t = rawType; t != Object.class; t = Types.getGenericSuperclass(t)) {
+      for (Type t = type; t != Object.class; t = Types.getGenericSuperclass(t)) {
         createFieldBindings(moshi, t, fields);
       }
       return new ClassJsonAdapter<>(classFactory, fields).nullSafe();
diff --git a/moshi/src/test/java/com/squareup/moshi/ClassJsonAdapterTest.java b/moshi/src/test/java/com/squareup/moshi/ClassJsonAdapterTest.java
index 5a6fa24..b6f5d7e 100644
--- a/moshi/src/test/java/com/squareup/moshi/ClassJsonAdapterTest.java
+++ b/moshi/src/test/java/com/squareup/moshi/ClassJsonAdapterTest.java
@@ -444,6 +444,23 @@ public final class ClassJsonAdapterTest {
     assertThat(fromJson.zipCode).isEqualTo("94043");
   }
 
+  static final class Box<T> {
+    final T data;
+
+    Box(T data) {
+      this.data = data;
+    }
+  }
+
+  @Test public void parameterizedType() throws Exception {
+    @SuppressWarnings("unchecked")
+    JsonAdapter<Box<Integer>> adapter = (JsonAdapter<Box<Integer>>) ClassJsonAdapter.FACTORY.create(
+        Types.newParameterizedTypeWithOwner(ClassJsonAdapterTest.class, Box.class, Integer.class),
+        NO_ANNOTATIONS, moshi);
+    assertThat(adapter.fromJson("{\"data\":5}").data).isEqualTo(5);
+    assertThat(adapter.toJson(new Box<>(5))).isEqualTo("{\"data\":5}");
+  }
+
   private <T> String toJson(Class<T> type, T value) throws IOException {
     @SuppressWarnings("unchecked") // Factory.create returns an adapter that matches its argument.
         JsonAdapter<T> jsonAdapter = (JsonAdapter<T>) ClassJsonAdapter.FACTORY.create(