Based on the GPS broadcast ephemeris parameters, the nonlinear least square fit algorithm of broadcast ephemeris parameters was developed, and the relevant calculation formulas were derived. Since geostationary satellite's orbit inclination is equal to zero approximately, it will result in the ambiguity of satellite's orbit ascending node and the singularity of the normal matrix in the process of fitting. By transforming the geostationary satellite's orbit inclination, the accuracy of broadcast ephemeris was achieved. Finally, the rationality of formulas and algorithm were validated by simulation.