The machining accuracy and the surface roughness of workpieces machined by the PKM named BJ-04-02(A) are evaluated by machining experiments in this paper. The machining accuracy includes that of size, shape and position. Size includes the diameter and length. Shape accuracy includes straightness, roundness and cylindricity. Position accuracy includes perpendicularity, parallelism, inclination and concentricity. The experiment results show that the surface roughness and the straightness basically meet the demand of JB/T8771.7-1998, but other accuracy indexes are not consistent well with the mechanical standard. However, the machining accuracy becomes bad when machining tool is far away from the center of the workspace.