condensation of headlamp, always complained by final customers, is regarded as one of the most difficult issue to solve among the automobile industries. Due to the special structure and temperature imbalance inside the headlamp, it is usually very hard to find a reasonable way to ensure all locations inside headlamp have same temperature, pressure and intensity, and therefore the possibili- ty to form condensation increase. Condensation is bad not only for the perceived quality, but also for the driving security during night. Current way to counter this phenomena is expensive or not so efficient. To find a cost-efficient way to improve headlamp condensa- tion, the paper focus on the mechanism analysis of condensation formation with methematical model of condensation core. By analyzing from the perspective of temperature field, intensity field and pressure field, the paper points out the root cause that leads to condensa- tion and summarizes the innovative approaches to eliminate the condensation based on the current know-how in automobile industry.