The effects of different sterilization methods and repeated freeze-thaw cycles on the quality of mulberry pulp were invesgtigated. Using unpasteurized mulberry pulp (Y) as the control in this experiment, the effects of pasteurization (TP), high-pressure processing (HPP), and five freeze-thaw cycles on the microbial content, conventional physicochemical indicators, anthocyanins, and flavor characteristics of mulberry pulp were compared. The results showed that both HPP and TP were effective in eliminating mold and yeast, with counts decreasing from 87 CFU/mL to undetectable levels, whereas only minor effects were observed on pH value, soluble solids content, and rheological properties. Among the treatments, HPP showed superior preservation of flavor and taste, exhibiting a 40.9% higher umami intensity than TP while limiting changes in the average particle size (D4,3) to less than 6%. Repeated freeze-thaw cycles inhibited microbial growth in both the Y and TP groups. The most pronounced changes in quality were observed after the first freeze-thaw cycle across all groups, characterized by increases in total acid and b* value, and decrease in a* value, and dynamic and static rheological properties. As the number of freeze-thaw cycles increased, the contents of total anthocyanin (1.33~1.70 mg•g-1) and total phenols (11.35~12.53 mgGAE•g-1) remained relatively stable, whereas variations in monomeric phenols were irregular. Furthermore, the aroma and taste were also affected to a certain extent by repeated freeze-thaw cycles. In conclusion, the quality of mulberry pulp was better preserved by HPP treatment. Repeated freeze-thaw cycles adversely affected pulp quality, with the greatest deterioration occurring during the first cycle. It is recommended that the TP and HPP groups should undergo no more than two and three freeze-thaw cycles, respectively. This study provides a theoretical foundation for the production and preservation of high-quality mulberry pulp.