Abstract: A p-type ZnSe bulk or film crystal of good quality has not been produced so far, although various improved methods based on MOCVD or MBE methods have been tried. Prior art required high pressure, high temperature or high vacuum to grow a p-type ZnSe crystal. This invention grows p-type ZnSe by an electrochemical deposition method. A zinc anode and a low-resistivity n-type ZnSe singlecrystalline substrate are immersed into a solution including zinc ions, selenium ions and acceptor ions. Direct current is sent from the zinc anode to the n-type ZnSe singlecrystalline substrate cathode. Selenium ions and zinc ions are attracted to the n-type ZnSe cathode. They are reduced and are deposited on the n-type ZnSe cathode. Deposited ZnSe film is a p-type semiconductor. A ZnSe semiconductor with a pn-junction is obtained.