The wettability of Betula alnoides was studied through dynamic contact angle measurement, Fourier transform infrared spectroscopy analysis, surface roughness measurement, scanning electron microscope observation and partial correlation analysis. The results showed that the wettability of Betula alnoides degrades after heat-treatment at 180 ℃ for 4 h since contact angle increases from 40 to 121 degree, the amount of hydroxyl and carbonyl reduce, and surface roughness decrease; teat-treatment has significant correlation with contact angle; heat treatment of Betula alnoides not only can remove harmful organisms, but also possesses hydrophobic function.