In this research work, hydrogen ion can be used for Schottky barrier height and surface potential tuning with specific power. The current output of Ohmic and Schottky contacted device would be enhanced from 8.25 μA to 171 μA and 2.84 pA to 1.3 μA (hydrogen plasma power was increased from 0 to 60 W), respectively. With adequate hydrogen plasma power, the transport mechanism (variation of Schottky barrier height and surface potential) can be studied in vacuum and atmosphere environment. In this work, we not only improve the current output but also provide the transport mechanism in vacuum and atmosphere environment. The enhancement and intension of ZnO nanowires device can be achieved by using hydrogen plasma treatment for extensive application.