Low-stress　Ni-Co　alloy　coatings　were　obtained　in　sulfate　bath　by　adding　proper　amount　of　butynediol　and　saccharin.　The　effect　of　butynediol　and　saccharin　concentration　on　cross-section　morphology,　microhardness,　structure　and　internal　stress　of　the　coating　was　investigated.　The　results　showed　that　butynediol　and　saccharin　could　lead　to　finer　grain,　higher　microhardness　and　stronger　(111)　plane.　Butynediol　could　produce　the　coating　contraction　and　tensile　stress,　while　saccharin　could　produce　the　coating　expansion　and　compressive　stress.　The　coating　internal　stress　range　from　64.64　MPa　to　-3.5　MPa　by　adding　0.08　g/L　butynediol　and　2　g/L　saccharin　to　the　sulfate　bath,　and　the　coating　had　high　microhardness　and　quality.