The work aims to reveal the influencing law of ammonium citrate concentration on element content, deposition rate, surface morphology and corrosion resistance of Ni-Cr-Mo alloy coating prepared by pulse electroplating. Ni-Cr-Mo alloy coatings were prepared on the surface of Q235 steel by pulse electroplating. The effects of ammonium citrate concentration on coating element content, deposition rate, surface morphology and corrosion resistance were inspected by glow discharge spectroscopy (GDS), X-ray diffraction (XRD), scanning electron microscopy (SEM), Tafel curve and electrochemical impedance spectroscopy (EIS). As ammonium citrate concentration increased, Cr content and Mo content increased; Ni content, deposition rate and the size of particles on coating surface decreased; corrosion resistance of coatings in 3.5% NaCl solution first increased and then decreased. Coating prepared in 196 g/L ammonium citrate bath had the highest corrosion potential(?0.537 V), the lowest corrosion current density (0.313 μA/cm2) and the highest charge transfer resistance (2075 ?·cm2), exhibiting the best corrosion resistance.