The work aims to design a new type of partially decoupled 2R1T parallel mechanism of RxPzRy type by an-alyzing the characteristics of the driving pairs of the partially decoupled 2R1T parallel mechanism by screw theory. Based on the input-output relationship of the fully decoupled parallel mechanism, the component of angular velocity of the moving platform in the axis direction of the fixed coordinate system was transformed into the component of XYZ Euler angular velocity. The fully decoupled block Jacobian matrix of angular velocity was obtained, and the partially decoupled input-output relationship of the mechanism with multiple rotational degrees of freedom was obtained. A new partially de-coupled 2R1T parallel mechanism was designed. The analysis showed that the mechanism was partially decoupled. For the decoupling design of RxPzRy type 2R1T parallel mechanism, the Jacobian matrix of angular velocity obtained by screw theory is not suitable for the complete decoupling design of parallel mechanism with multiple rotational degrees of freedom. The Jacobian matrix of Euler angular velocity is transformed by the proposed transformation matrix to obtain the corresponding diagonal matrix. The proposed method can be used for the complete decoupling design of parallel mechanisms with multiple rotational degrees of freedom.