Electromagnetic induction heating has many advantages such as fast heating, low energy consumption and environmental pollution reduction. Using induction heating for rapid tool heating is more economic and efficient than any of the tool heating technique. Previous studies using electromagnetic induction heating for rapid tool heating indicate that the temperature uniformity on cavity surface is not easy to be achieved no matter with surface or insert type induction heating. In this paper, a series of experiments were conducted to study the effectiveness of temperature uniformity on mold cavity surface for different induction heating coil. The parallel type coil and magnetic flux concentrators were adopted to form the induction heating device. According to the results of heating experiments, the surface temperature of 10 mm thickness hot work die steel (JIS SKD61) could rise from 50°C to 150°C in 15 seconds and the temperature uniformity of the heated zone reached 94%-95%.