diff --git a/src/passes/operators/operators.ml b/src/passes/operators/operators.ml
index 9446ed3df..6a56721d8 100644
--- a/src/passes/operators/operators.ml
+++ b/src/passes/operators/operators.ml
@@ -107,6 +107,7 @@ module Simplify = struct
       | "map_remove"      -> ok C_MAP_REMOVE
       | "map_update"      -> ok C_MAP_UPDATE
       | "map_get"         -> ok C_MAP_GET
+      | "map_mem"         -> ok C_MAP_MEM
       | "sha_256"         -> ok C_SHA256
       | "sha_512"         -> ok C_SHA512
       | "blake2b"         -> ok C_BLAKE2b
@@ -203,6 +204,7 @@ module Simplify = struct
       | "Map.iter"                 -> ok C_MAP_ITER
       | "Map.map"                  -> ok C_MAP_MAP
       | "Map.fold"                 -> ok C_MAP_FOLD
+      | "Map.mem"                  -> ok C_MAP_MEM
       | "Map.empty"                -> ok C_MAP_EMPTY
       | "Map.literal"              -> ok C_MAP_LITERAL
       | "Map.size"                 -> ok C_SIZE
@@ -913,6 +915,7 @@ module Compiler = struct
     | C_MAP_GET_FORCE   -> ok @@ simple_binary @@ seq [prim I_GET ; i_assert_some_msg (i_push_string "GET_FORCE")]
     | C_MAP_FIND        -> ok @@ simple_binary @@ seq [prim I_GET ; i_assert_some_msg (i_push_string "MAP FIND")]
     | C_MAP_GET         -> ok @@ simple_binary @@ prim I_GET
+    | C_MAP_MEM         -> ok @@ simple_binary @@ prim I_MEM
     | C_MAP_FIND_OPT    -> ok @@ simple_binary @@ prim I_GET
     | C_MAP_ADD         -> ok @@ simple_ternary @@ seq [dip (i_some) ; prim I_UPDATE]
     | C_MAP_UPDATE      -> ok @@ simple_ternary @@ prim I_UPDATE
diff --git a/src/test/contracts/map.ligo b/src/test/contracts/map.ligo
index 7f53005cd..797bb1a8b 100644
--- a/src/test/contracts/map.ligo
+++ b/src/test/contracts/map.ligo
@@ -47,6 +47,8 @@ function get_ (const m : foobar) : option(int) is
     skip
   end with map_get(42 , m)
 
+function mem (const k: int; const m: foobar) : bool is map_mem(k, m)
+
 function iter_op (const m : foobar) : unit is
   block {
     function aggregate (const i : int ; const j : int) : unit is block
diff --git a/src/test/contracts/map.mligo b/src/test/contracts/map.mligo
index 85592acb1..a3de0cdb6 100644
--- a/src/test/contracts/map.mligo
+++ b/src/test/contracts/map.mligo
@@ -28,6 +28,8 @@ let gf (m: foobar) : int = Map.find 23 m
 let get (m: foobar) : int option = Map.find_opt 42 m
 let get_ (m: foobar) : int option = Map.find_opt 42 m
 
+let mem (km: int * foobar) : bool = Map.mem km.0 km.1
+
 let iter_op (m : foobar) : unit =
   let assert_eq = fun (i: int) (j: int) -> assert (i=j)
   in Map.iter assert_eq m
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index 725db8ddd..d467eefee 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -663,6 +663,14 @@ let map_ type_f path : unit result =
     let make_expected = fun _ -> e_some @@ e_int 4 in
     expect_eq_n program "get_" make_input make_expected
   in
+  let%bind () = 
+    let input_map = ez [(23, 10) ; (42, 4)] in
+    expect_eq program "mem" (e_tuple [(e_int 23) ; input_map]) (e_bool true)
+  in
+  let%bind () =
+    let input_map = ez [(23, 10) ; (42, 4)] in
+    expect_eq program "mem" (e_tuple [(e_int 1000) ; input_map]) (e_bool false)
+  in
   let%bind () = expect_eq_evaluate program "empty_map"
     (e_annotation (e_map []) (t_map t_int t_int)) in
   let%bind () =