Nanocrystalline　Ni-Fe　alloy　coatings　were　synthesized　by　brush　plating　using　soluble　anode.　Microhardness　test　and　techniques　of　XRD,　SEM　and　TEM　were　applied　to　characterize　the　microstructures　and　mechanical　properties　of　Ni-Fe　alloy　coatings.　The　results　show　that　the　microhardness　of　Ni-Fe　alloy　coatings　increases　with　increasing　annealing　temperature　and　reaches　a　peak　value　at　200°C,　showing　a　significant　hardening　during　annealing.　With　further　increasing　annealing　temperature,　the　microhardness　decreases　gradually,　but　the　microhardness　of　the　coating　after　being　annealed　at　400°C　is　still　as　high　as　that　of　the　as-deposited　sample.　The　abnormal　grain　growth　is　not　observed　during　annealing　of　Ni-Fe　alloy　coatings,　which　indicates　a　better　thermal　stability.