Abstract: In the early time of the 21st century the power transmission system of aeroengine still will be based on mechanical transmission,and will face the challenges of advanced aeroengine in respect to mainshaft bearing,lubricating,gear transmission and sealing.The researches on the electro magnetic bearings and the electro driving accessories,which will be used on future aeroengines,are just unfolded.This paper also introduces the development work and targets of the key laboratory of aeroengine power transmission in brief.