Based on the theory of position and orientation characteristics (POC) set, the minimum range POC set of serial branch with both 1T2R and 2T1R motion mode was indentified, many novel branches with two motion modes were synthesized. A conbined schemes of parallel mechanism with both 1T2R and 2T1R motion mode was completed by referring to correration of maximum linear vector, finally. Under different motion mode, the kinematical feature of the optimal parallel mechanism with two motion mode was analyzed. The research results show that when the synthetical parallel mechanism is driven under the premise of one of the revolution pairs of the bifurcated branch is locked, motion mode shift from 1T2R to 2T1R can be finished through the bifurcated position.