The work aims to propose a novel 2-UCU/U parallel drive bidirectional rotating mechanical arm applied to large component printing to make the working end of the mechanical arm reach a specific position in a plane or a curved surface. The constrained screw of 2-UCU/U mechanism was analyzed with screw theory. The degree of freedom property of the mechanism was obtained, and the rationality of the input selection was verified. The inverse position solution of the mechanism was obtained with the closed vector method, and the velocity Jacobian matrix was established. The workspace of the mechanism was obtained with search method with the help of Matlab. The motion relationship between input and output of the mechanism was analyzed. The workspace of 2-UCU/U parallel driving bidirectional rotating mechanical arm was solved, and its shape was spherical surface. Analysis showed that the motion of the mechanism was rotation in both pitch and yaw directions. The same direction movements of the driving pairs realize the pitching movement of the working arm, and the reverse direction movements of the driving pairs realize the yawing movement of the working arm. Therefore, the working arm can reach the required position of the working surface, and finally the tool connected to the end of the working arm can work at a specific position.