Microwave vacuum drying of blackberry was carried out to investigate the effect of microwave power and vacuum degree on the temperature of blackberry during drying process, and the distribution law of the whole temperature field was observed. Using numerical simulation method, the coupling model of electromagnetic and heat transfer was established. After two minutes of microwave vacuum heating, the simulation temperature field distributions of blackberry under different microwave power and vacuum degree conditions were obtained. The experiment was carried out under the condition of microwave power of 400 W and vacuum degree of -60 kPa, and the experiment and simulation results were compared to analyze and evaluate the results of numerical simulation. Simulation can observe and avoid the hot and cold spots. The appropriate microwave power and vacuum were also selected by simulation to reduce the temperature difference and ensure heating uniformity. The results showed that blackberry under the condition of the microwave power of 400 W and vacuum degree of -80 kPa after heating 2 min, the temperature of the hot spot was maintained at about 60 ℃, with the temperature difference about 0.27. The heating uniformity was consequently ensured to meet the drying requirements of the blackberry.