diff --git a/src/indexmap.rs b/src/indexmap.rs
index ed5b35e7..05cec4cd 100644
--- a/src/indexmap.rs
+++ b/src/indexmap.rs
@@ -781,6 +781,34 @@ where
     }
 }
 
+impl<K, V, N, S, N2, S2> PartialEq<IndexMap<K, V, N2, S2>> for IndexMap<K, V, N, S>
+where
+    K: Eq + Hash,
+    V: Eq,
+    S: BuildHasher,
+    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
+    S2: BuildHasher,
+    N2: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
+{
+    fn eq(&self, other: &IndexMap<K, V, N2, S2>) -> bool {
+        self.len() == other.len()
+            && self
+                .iter()
+                .all(|(key, value)| other.get(key).map_or(false, |v| *value == *v))
+    }
+}
+
+impl<K, V, N, S> Eq for IndexMap<K, V, N, S>
+where
+    K: Eq + Hash,
+    V: Eq,
+    S: BuildHasher,
+    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
+{
+
+}
+
+
 impl<K, V, N, S> Extend<(K, V)> for IndexMap<K, V, N, S>
 where
     K: Eq + Hash,
@@ -944,4 +972,35 @@ mod tests {
                 mem::size_of::<usize>() // entries.length
         )
     }
+
+
+    #[test]
+    fn partial_eq() {
+        {
+            let mut a: FnvIndexMap<_, _, U4> = FnvIndexMap::new();
+            a.insert("k1", "v1").unwrap();
+
+            let mut b: FnvIndexMap<_, _, U4>  = FnvIndexMap::new();
+            b.insert("k1", "v1").unwrap();
+
+            assert!(a == b);
+
+            b.insert("k2", "v2").unwrap();
+
+            assert!(a != b);
+        }
+
+        {
+            let mut a: FnvIndexMap<_, _, U4>  = FnvIndexMap::new();
+            a.insert("k1", "v1").unwrap();
+            a.insert("k2", "v2").unwrap();
+
+            let mut b: FnvIndexMap<_, _, U4>  = FnvIndexMap::new();
+            b.insert("k2", "v2").unwrap();
+            b.insert("k1", "v1").unwrap();
+
+            assert!(a == b);
+        }
+    }
+
 }