Abstract: It is of extensive significance to establish a GPS space baseline vector network for the improvement of an exisiting terrestril network,the analysis of systematic errors of the network and the monitoring of geodynamics.In this paper,the methods and models for threedimensional combined adjustment of the space baseline vector network and the terrestrial control network are discussed in great detail along with those for the twodimensional combined adjustment.It has been pointed out that the combined adjustment method for the two networks in twodimensional geodetic coordinate system is of practical importance in order to avoid the effects on the results of threedimensional combined adjustment resulting from the errors of heights of the terrestrial network and the model errors due to the introduction of scale factor to the network.