To provide alloy plating suitable for forming the electric contact of a connector or the like, capable of obtaining a contact resistance value close to that of pure gold, and capable of obtaining a satisfactory plating film.

The gold-silver alloy plating liquid for an electric contact comprises gold potassium cyanide by 1.0 to 30 g/l in terms of a gold content and silver potassium cyanide by 1.0 to 200 ppm in terms of a silver content. The plating liquid is preferably admixed with potassium pyrophosphate by 30 to 100 g/l, boric acid by 20 to 50 g/l and ethylenediamine or the derivative thereof by 0.05 to 150 g/l. The electroplating is performed under the conditions satisfying a liquid temperature of 20 to 70C and a current density of 10 to 110 A/dm2.