The goal of this paper is to investigate the variation of hardness of the re-melted deposited surface by direct energy deposition (DED) processes. Re-melting experiments of the deposited specimen are performed using a plasma electron beam system. The acceleration voltage and the number of irradiation of the electron beam are chosen as process parameters. The surface hardness are measured by a nano-indentator. The effects of process parameters on the hardness of the re-melted region are examined. In addition, hardening characteristics of the re-melted surface is discussed.