As core functional components of the medium and high grade CNC machine tools, the power-driven turret involves high technology and complicated structures. Traditionally, in the study of low speed turrets` performances, the effects of thermal influences are often negligible. However, on the high speed conditions, thermal effect cannot be neglected. This paper establishes the high speed turret 3-D Model and the Finite Element Model (FEM), and investigates and analyzes temperature fields and thermal deformations. Experimental measurements are implemented on the surfaces of the original model turret in order to compare with the simulation results, modified turret is analyzed, and thermal behaviors are proved to be available on the idle operating conditions. It manifests that the distributions of the thermal behaviors have intensive relations with the speeds of the transmission system.