Limited motion range and easily happened rotation axis drift are the main disadvantages of traditional flexible joint of parallel robot. In order to promote the performance of flexure joint, a new design of open thin-walled flexure joint was proposed. According to the range of motion of 3RRR parallel robot, the geometry of joint was calculated by using the motion range of joint and the required joint stiffness as design parameters. And the structure strength of joint was analyzed via ANSYS. Torsion is the deformation mode of the open thin-walled flexure joint. The advantages of 36 degrees motion range and fixed rotation axis are presented in this joint. The practical joint is made of 65Mn spring steel according to the designed joint geometry. The contrast experiments between leaf spring and open thin-walled flexure joints were carried out on a three DOF parallel robot experiment platform. The results show the designed open thin walled flexure joint can accomplish trajectory tracking missions and the maximum relative error is 6。05%. Its superiority over the leaf spring joint is presented by the results.