Abstract: In order to solve the problem of temperature inhomogeneity of heating medium in leather shrinkage temperature measuring instrument, the characteristics and laws of temperature field were studied. Firstly, the test scheme of temperature field distribution was designed based on MSW-YD4, and the distribution mode of PT100 temperature sensor was given. Then, the temperature tests were carried out in the same heating medium in the horizontal and vertical directions, and in different heating media in the state of mixing or not and under the composite control. Finally, the space-time distribution of temperature field was given under different conditions. The experimental results show that the horizontal temperature field of heating medium was uniform and the error was small, while the vertical temperature error was large, but the error decreased gradually with the heating process. The increase of agitation could accelerate the flow and make the temperature distribution more uniform, and the compound control method can effectively reduce the temperature fluctuation of heating medium during the heating process. This rule can provide an effective basis for the improvement and optimization of the leather shrinkage temperature measuring instrument, and then improve the measuring accuracy of leather shrinkage temperature.