Abstract: A new concept of phasing orbit was adopted in the orbit design for the first Chinese lunar satellite.The phasing orbit established a connection between super GTO,which is inserted by the launch vehicle CZ-3A,and the trans-lunar trajectory.In order to make the conjoint orbit more accurate,the orbital perturbations caused by earth gravitational field should be taken into consideration.For doing so making use of the solution to the classical general perturbation theory is a good choice.Based on the solution,we can perform transformation between the osculation elements and the mean orbits.First transfer GTO into mean orbit,then connect it to mean phasing orbits,after that transform back to osculation one and connect with translunar-trajectory.