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A hybrid variable degree of freedom (DoF) branched chain was proposed after that moving platform of the parallel mechanism with 2R1T and 2T1R motion modes was connected with the planar parallelogram mechanism in series. The motion modes of series variable degree of freedom branched chains and hybrid variable degree of freedom branched chains were analyzed. A mechanism with series and hybrid variable DoF branching chains was constructed. The DoF characteristics of the parallel mechanism in the process of motion mode transformation were analyzed by using screw theory, and the rationality of the selection of driving pairs in different motion modes was verified. When calculating the degree of freedom of mechanism and selecting the reasonable driving pair of mechanism, different rods were selected as the moving platform to simplify the analysis process. The results showed that the mechanism with hybrid variable DoF kinematic chain had 3T, 2T1R and 2R1T motion modes. When the mechanism was in the general configuration of the three motion modes mentioned above, three driving pairs can control the mechanism. When the mechanism was transformed from 3T motion mode to 2T1R motion mode, it needed to pass through 3T1R instantaneous DoF configuration. When the mechanism was transformed from 2T1R motion mode to 2R1T motion mode, the mechanism needed to pass through 2R2T instantaneous DoF configuration. When the mechanism was in the transformation configuration which had 3T1R or 2R2T instantaneous DoF, the mechanism was in constrained singularity configuration, and an additional auxiliary driving pair was needed to control the mechanism. The mechanism can realize multiple motion modes by using fewer driving pairs. It did not need to reassemble the mechanism when the motion mode was changed.