Abstract: A method is put forward,which is based on single point positioning to(eliminate) the satellite constellation revolving errors round the earth and systematic error ΔΩ in all satellite clocks in making autonomous orbit determination with distance and velocity observations among satellites.When all navigation satellites revolve an angel ΔΩ round the earth,the longitude of the station given by point positioning will deviate the same angel.According to this principle,we can determine the angel ΔΩ on ground station with accurate coordinates.When all satellite clocks contain the same systematic error,the clock bias of receiver determined by point positioning also contains the same time error Δt.Then the error Δt can be determined by comparing with standard time.The results of several examples show that the methods is feasible and practicable.