A new type of parallel mechanism with three dimensional (3D) translations and movement complete decoupling was generated by changing the configuration form of the movement branched chains of the original 3-CRC parallel mechanism，and the positional forward and inverse solution equations were derived.The analytical expression of workspace of mechanism was derived from using the complete decoupling and positional equations of the mechanism, and the decoupling performance and workspace of two types of mechanisms were compared.The excellent kinematics performance of the new mechanisms is verified, which provides a basis for further application and study.