diff --git a/apps/mappingmanagement/api/src/test/java/org/onosproject/mapping/codec/MappingKeyCodecTest.java b/apps/mappingmanagement/api/src/test/java/org/onosproject/mapping/codec/MappingKeyCodecTest.java
new file mode 100644
index 0000000..25d6ff4
--- /dev/null
+++ b/apps/mappingmanagement/api/src/test/java/org/onosproject/mapping/codec/MappingKeyCodecTest.java
@@ -0,0 +1,166 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.mapping.codec;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.hamcrest.Description;
+import org.hamcrest.TypeSafeDiagnosingMatcher;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onlab.packet.IpPrefix;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.codec.impl.CodecManager;
+import org.onosproject.mapping.DefaultMappingKey;
+import org.onosproject.mapping.MappingKey;
+import org.onosproject.mapping.addresses.MappingAddress;
+import org.onosproject.mapping.addresses.MappingAddresses;
+import org.onosproject.mapping.MappingCodecRegistrator;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+
+/**
+ * Unit tests for MappingKeyCodec.
+ */
+public class MappingKeyCodecTest {
+
+    private static final String IPV4_STRING = "1.2.3.4";
+    private static final String PORT_STRING = "32";
+    private static final IpPrefix IPV4_PREFIX =
+                         IpPrefix.valueOf(IPV4_STRING + "/" + PORT_STRING);
+
+    private CodecContext context;
+    private JsonCodec<MappingKey> keyCodec;
+    private MappingCodecRegistrator registrator;
+
+    /**
+     * Sets up for each test.
+     * Creates a context and fetches the mapping key codec.
+     */
+    @Before
+    public void setUp() {
+        CodecManager manager = new CodecManager();
+        registrator = new MappingCodecRegistrator();
+        registrator.codecService = manager;
+        registrator.activate();
+
+        context = new MappingCodecContextAdapter(registrator.codecService);
+        keyCodec = context.codec(MappingKey.class);
+        assertThat(keyCodec, notNullValue());
+    }
+
+    /**
+     * Deactivates the codec registrator.
+     */
+    @After
+    public void tearDown() {
+        registrator.deactivate();
+    }
+
+    /**
+     * Tests encoding of a mapping key object.
+     */
+    @Test
+    public void testMappingKeyEncode() {
+
+        MappingAddress address = MappingAddresses.ipv4MappingAddress(IPV4_PREFIX);
+
+        MappingKey key = DefaultMappingKey.builder()
+                                .withAddress(address)
+                                .build();
+
+        ObjectNode keyJson = keyCodec.encode(key, context);
+        assertThat(keyJson, MappingKeyJsonMatcher.matchesMappingKey(key));
+    }
+
+    /**
+     * Tests decoding of a mapping key JSON object.
+     */
+    @Test
+    public void testMappingKeyDecode() throws IOException {
+        MappingKey key = getKey("MappingKey.json");
+        assertThat(key.address().toString(),
+                            is("IPV4:" + IPV4_STRING + "/" + PORT_STRING));
+    }
+
+    /**
+     * Hamcrest matcher for mapping key.
+     */
+    public static final class MappingKeyJsonMatcher
+            extends TypeSafeDiagnosingMatcher<JsonNode> {
+
+        private final MappingKey mappingKey;
+
+        /**
+         * A default constructor.
+         *
+         * @param mappingKey mapping key
+         */
+        private MappingKeyJsonMatcher(MappingKey mappingKey) {
+            this.mappingKey = mappingKey;
+        }
+
+        @Override
+        protected boolean matchesSafely(JsonNode jsonNode, Description description) {
+
+            // check address
+            final JsonNode jsonAddressNode = jsonNode.get(MappingKeyCodec.ADDRESS);
+
+            assertThat(jsonAddressNode,
+                    MappingAddressJsonMatcher.matchesMappingAddress(mappingKey.address()));
+
+            return true;
+        }
+
+        @Override
+        public void describeTo(Description description) {
+            description.appendText(mappingKey.toString());
+        }
+
+        /**
+         * Factory to allocate a mapping treatment.
+         *
+         * @param mappingKey mapping treatment object we are looking for
+         * @return matcher
+         */
+        static MappingKeyJsonMatcher matchesMappingKey(MappingKey mappingKey) {
+            return new MappingKeyJsonMatcher(mappingKey);
+        }
+    }
+
+    /**
+     * Reads in a mapping key from the given resource and decodes it.
+     *
+     * @param resourceName resource to use to read the JSON for the rule
+     * @return decoded mappingKey
+     * @throws IOException if processing the resource fails
+     */
+    private MappingKey getKey(String resourceName) throws IOException {
+        InputStream jsonStream = MappingKeyCodecTest.class.getResourceAsStream(resourceName);
+        JsonNode json = context.mapper().readTree(jsonStream);
+        assertThat(json, notNullValue());
+        MappingKey key = keyCodec.decode((ObjectNode) json, context);
+        assertThat(key, notNullValue());
+        return key;
+    }
+}