Abstract: he continuous wave radar system is the main equipment for high precision orbit observing at present.Effected by various factors,the time at different observation station are not all coincide,which leads to errors in the setimation of orbits.By detailed analysis of the observation principles and the time errors,with the advantages of the polynomial representation of the orbit,we establish a nonlinear regression model to estimate the time errors and the coefficients of the orbit polynomials.Further more,a method for parameter estimation and the errors of the estimations are presented.Theory analysis and practical examples show that our method offers higher precision for the estimation of orbits and time errors.