The work aims to find the most suitable pretreatment method to obtain the dry products with the highest sensory score. Drying rate, volume shrinkage rate, color difference, browning degree and sensory score were taken as evaluation indexes to analyze the effects of five pretreatment methods (blanching, steaming, ultrasonic, osmotic and freeze-thaw) on the drying quality of pitaya by heat pump. The drying rate and volume shrinkage rate of all pitaya after pretreatment in experimental group were higher than those of the control group without pretreatment. The drying rate and volume shrinkage rate of the experimental group after one freeze-thaw pretreatment were the largest, and the drying time and volume were reduced by 76.6% and 93.3% respectively. After 0.2% zinc acetate osmotic pretreatment, the browning degree of the experimental group was the lowest, which was 24.893 and 17.225 respectively. The weight set obtained by the fuzzy comprehensive evaluation method was W= (0.23, 0.33, 0.26, 0.18). Based on the weight set, it was calculated that the sensory score of the experimental group with 0.2% zinc acetate osmotic pretreatment was the highest, reaching 71.55. The quality of pitaya is the best after osmotic pretreatment with 0.2% zinc acetate.