diff --git a/mlx/backend/cpu/unary_ops.h b/mlx/backend/cpu/unary_ops.h
index aab1e0de2..633230658 100644
--- a/mlx/backend/cpu/unary_ops.h
+++ b/mlx/backend/cpu/unary_ops.h
@@ -86,13 +86,14 @@ struct Sign {
   template <int N, typename T>
   Simd<T, N> operator()(Simd<T, N> x) {
     auto z = Simd<T, N>{0};
+    auto o = Simd<T, N>{1};
+    auto m = Simd<T, N>{-1};
     if constexpr (std::is_unsigned_v<T>) {
-      return x != z;
+      return simd::select(x == z, z, o);
     } else if constexpr (std::is_same_v<T, complex64_t>) {
       return simd::select(x == z, x, Simd<T, N>(x / simd::abs(x)));
     } else {
-      return simd::select(
-          x < z, Simd<T, N>{-1}, simd::select(x > z, Simd<T, N>{1}, z));
+      return simd::select(x < z, m, simd::select(x > z, o, z));
     }
   }
   SINGLE()
diff --git a/tests/ops_tests.cpp b/tests/ops_tests.cpp
index b8bc8b45e..356515702 100644
--- a/tests/ops_tests.cpp
+++ b/tests/ops_tests.cpp
@@ -1241,6 +1241,47 @@ TEST_CASE("test arithmetic unary ops") {
     // bool
     x = array({false, true});
     CHECK(array_equal(sign(x), x).item<bool>());
+
+    // uint64
+    array x_uint64(
+        {uint64_t(0xa11cc311cb6acd70),
+         uint64_t(0x7a375ac3ebb533f3),
+         uint64_t(0x734969adf9d7190c),
+         uint64_t(0xb400515a4f673424)});
+    array expected(
+        {uint64_t(0x0000000000000001),
+         uint64_t(0x0000000000000001),
+         uint64_t(0x0000000000000001),
+         uint64_t(0x0000000000000001)});
+    CHECK(array_equal(sign(x_uint64), expected).item<bool>());
+
+    x_uint64 = array(
+        {uint64_t(0xa11cc311cb6acd70),
+         uint64_t(0x7a375ac3ebb533f3),
+         uint64_t(0x734969adf9d7190c)});
+    expected = array(
+        {uint64_t(0x0000000000000001),
+         uint64_t(0x0000000000000001),
+         uint64_t(0x0000000000000001)});
+    CHECK(array_equal(sign(x_uint64), expected).item<bool>());
+
+    x_uint64 =
+        array({uint64_t(0xa11cc311cb6acd70), uint64_t(0x7a375ac3ebb533f3)});
+    expected =
+        array({uint64_t(0x0000000000000001), uint64_t(0x0000000000000001)});
+    CHECK(array_equal(sign(x_uint64), expected).item<bool>());
+
+    x_uint64 = array({uint64_t(0xa11cc311cb6acd70)});
+    expected = array({uint64_t(0x0000000000000001)});
+    CHECK(array_equal(sign(x_uint64), expected).item<bool>());
+
+    x_uint64 = array({uint64_t(0xffffffffffffffff)});
+    expected = array({uint64_t(0x0000000000000001)});
+    CHECK(array_equal(sign(x_uint64), expected).item<bool>());
+
+    x_uint64 = array({uint64_t(0x0000000000000001)});
+    expected = array({uint64_t(0x0000000000000001)});
+    CHECK(array_equal(sign(x_uint64), expected).item<bool>());
   }
 
   constexpr float neginf = -std::numeric_limits<float>::infinity();