In order to solve the thermal deformations of ball screw, the hollow ball screw with cooling oil system was put forward to the problem. Theoretical friction heat and thermal boundary conditions were calculated, the results of which were loaded on hollow/solid ball screw with the same stiffness in ANSYS, which is a Finite Element Analysis (FEA) software, and then the analysis on the relations between the temperature rise and loading of the ball screw, and temperature and flow velocity of cooling oil was proceeded. Finally the deformations conditions of both ball screws were compared with analysis. The results show that the hollow ball screw with cooling oil works even better than the solid one while under highspeed and highload conditions.