The mass transport of Au ultrathin film on a semiconductor MoS2 was investigated by atomic force microscopy (AFM) and scanning Auger microscopy (SAM). The surface electromigration of the Au film was found when a de current was passed through the MoS2 substrate. The Au ultrathin film on MoS2 grew in a typical Volmer-Weber (V-W) growth mode, The AFM measurements indicated that the distribution of the Au islands exhibited clearly a preferential lateral spread towards the cathode, that is, the surface electromigration took place. The direction of the surface electromigration on MoS2 is opposite to that of the Au electromigration on Si.