Experiment on the surface characteristics of polymer films treated by atmospheric pressure plasma has been conducted. We chose the process parameters as frequency, gas flow, treatment time, and scrutinized the effects of the process parameters on the surface characteristics of polymer materials by measuring the contact angle and examining SEM. As the result, the surface characteristics highly depends on frequency, reaction gas and treatment time. In the case of PC substrate, the contact angle was changed from $83.5^{circ}$ (before plasma treatment) to $30^{circ}$ (after plasma treatment) at 30 kHz, CDA 0.6%, and number of repeat 7. In the case of PET substrate, the contact angle change was found from $59^{circ}$ to $23.5^{circ}$ at 20 kHz, CDA 0.6%, and number of repeat 7. In the case of EVA substrate, it shows from $84^{circ}$ to $44.2^{circ}$ at 30 kHz, CDA 0.6%, and number of repeat 7.