diff --git a/src/firestore-query.js b/src/firestore-query.js
index e2b275db..5e957965 100644
--- a/src/firestore-query.js
+++ b/src/firestore-query.js
@@ -126,7 +126,7 @@ MockFirestoreQuery.prototype.where = function (property, operator, value) {
   var query;
 
   // check if unsupported operator
-  if (operator !== '==') {
+  if (operator !== '==' && operator != 'array-contains') {
     console.warn('Using unsupported where() operator for firebase-mock, returning entire dataset');
     return this;
   } else {
@@ -139,6 +139,11 @@ MockFirestoreQuery.prototype.where = function (property, operator, value) {
               results[key] = _.cloneDeep(data);
             }
             break;
+          case 'array-contains':
+            if (_.includes(_.get(data, property), value)) {
+              results[key] = _.cloneDeep(data);
+            }
+            break;
           default:
             results[key] = _.cloneDeep(data);
             break;
diff --git a/test/unit/data.json b/test/unit/data.json
index dd566989..6b2ae7ab 100644
--- a/test/unit/data.json
+++ b/test/unit/data.json
@@ -90,6 +90,7 @@
     "b": {
       "name": "b",
       "name_type": "string",
+      "array": ["x"],
       "complex": {
         "name": "b"
       }
@@ -97,6 +98,7 @@
     "c": {
       "name": "c",
       "name_type": "string",
+      "array": ["y"],
       "complex": {
         "name": "c"
       }
@@ -104,12 +106,14 @@
     "1": {
       "name": 1,
       "name_type": "number",
+      "array": ["xx"],
       "complex": {
         "name": 1
       }
     },
     "2": {
       "name": 2,
+      "array": ["x", "y"],
       "name_type": "number",
       "complex": {
         "name": 2
@@ -119,7 +123,8 @@
       "name": 3,
       "name_type": "number",
       "complex": {
-        "name": 3
+        "name": 3,
+        "array": ["x"]
       }
     }
   },
diff --git a/test/unit/firestore-collection.js b/test/unit/firestore-collection.js
index 2e4c8d47..ad69f52c 100644
--- a/test/unit/firestore-collection.js
+++ b/test/unit/firestore-collection.js
@@ -215,6 +215,8 @@ describe('MockFirestoreCollection', function () {
       var results5 = collection.where('name_type', '==', 'number').get();
       var results6 = collection.where('name_type', '==', 'abc').get();
       var results7 = collection.where('value', '==', 3).get();
+      var results8 = collection.where('array', 'array-contains', 'x').get();
+      var results9 = collection.where('array', 'array-contains', 'z').get();
       db.flush();
 
       return Promise.all([
@@ -224,7 +226,9 @@ describe('MockFirestoreCollection', function () {
         expect(results4).to.eventually.have.property('size').to.equal(3),
         expect(results5).to.eventually.have.property('size').to.equal(3),
         expect(results6).to.eventually.have.property('size').to.equal(0),
-        expect(results7).to.eventually.have.property('size').to.equal(0)
+        expect(results7).to.eventually.have.property('size').to.equal(0),
+        expect(results8).to.eventually.have.property('size').to.equal(2),
+        expect(results9).to.eventually.have.property('size').to.equal(0)
       ]);
     });