Abstract: With air and water as medium, a numerical analysis of gas-liquid two-phase flow and heat transfer characteristics in serpentine micro-channel was made using the CLSVOF (coupled level set and volume of fluid) method multiphase model. After verifying the rationality of the model with the experiment, by changing the relative roughness and Re, the influences of them on Po and Nu were discussed, and the influence mechanism was analyzed. In means of changing the contact angle and relative roughness of the wall, the combined effect of them on fluid flow in micro-channel was discussed. Flow characteristics for several kinds of channel combinations with different wall surfaces were studied because of the unique curve part of serpentine micro-channel. The calculation results show that the increase of relative roughness has greater influence on Po than Nu, and can enhance heat transfer. The effects of relative roughness on hydrophilic wall and hydrophobic wall are opposite. When the straight part is hydro-philic smooth wall and the curve part is hydrophobic rough surface, the heat transfer is better.