The three-dimensional simulation of transformer thermal fluid field is an important method to accurately calculate the hot spot temperature of transformer winding. In this paper, a three-dimensional simulation model of S13-M.Rl-100kVA/10kV stereoscopic winding core transformer is built, and the temperature field distribution of the transformer under different load rates is calculated. At the same time, the calculation results are verified by transformer short-circuit temperature rise test. In the test, the temperature of transformer winding is measured by laying optical fiber temperature sensors in the transformer winding, and thermal resistance temperature sensors are set to measure the temperature on transformer iron shell. the maximum error between the temperature simulation results of each temperature monitoring point and the test results is less than 3 ℃, which proves that the transformer temperature fluid field simulation model proposed in this paper has a good validity and accuracy.