Adjusting the rotor rotation speed reasonably along with flight states can reduce demand power and fuel consumption, thus benefit flight performance. We evaluated the effect of the variable speed rotor on endurance performance, and analyzed stepless speed change and step speed change. The level 1 and level 2 variable speed method were put forward. The research results indicated that optimized rotation speed can upgrade endurance performance obviously. Compared with the rated speed, it can reduce profile power. The level 1 variable speed method is more fit for engineering application.