A new type of 3-PPR spherical parallel mechanism is proposed.Due to the mobile pair special trajectory in each branch chain,the mobile pair can be equivalent conversion for revolute pair.Based on screw theory,each branched chain motion screw system is given.The mobility of this mechanism is analyzed firstly with the amendment G-K formula,The numbers of degrees of freedom is obtained.Secondly,by using the solution method of inverse spiral system and matrix theory knowledge,under the premise of Jacobian matrix of the 3-PPR spherical parallel mechanism is solved,the rank of matrix is analyzed,the singular configuration conditions and the type of singular configuration of the mechanism are obtained.In the end,according to the forward kinematics solution and interference condition,the Matlab software is used to draw up the stable working space.Research shows that a 3-PPR parallel spherical mechanism singularity is less,and easy to avoid,has good application prospect.