The surface of a p-MoSe2 electrode has been observed in 0.05 M HNO3, in situ, by electrochemical scanning tunneling microscopy (ECSTM). Randomly oriented nanometer size spots have been observed on the surface. The STM images of the p-MoSe2 surface have been found to change with the electrode potential. That is, the nanometer size spots appeared as a dark contrast under a smaller band bending condition (0.2 V versus SCE) while the spots disappeared or further appeared as bright contrast under a larger band bending condition (0 and -0.2 V versus SCE). This is presumed to result from whether the acceptor level, within the band gap of the p-MoSe2, is occupied or not. In addition, it will depend on the electrode potential, which determines the amount of the band bending.