In order to explore the effect of freeze-thaw cycles on tuna meat,physicochemical properties,such as thawing loss,a* value,textural properties-Hardness,Cohesiveness,Springiness and Chewines,volatile odor(Electronic nose),total viable count(TVC) were carried out.Yellowfin tuna(stored at-18℃,-60℃,respectively) was subjected to a total of 4 freeze-thaw cycles.The results showed that with the number of freeze-thaw cycles increased,thawing loss increased and the highest was at-60℃.a* value decreased significantly after 4 freeze-thaw cycles at-18℃,and showed no significant change at-60℃.Hardness,Springiness and Chewiness decreased significantly,while Cohesiveness remained unchanged.Electronic nose analysis showed that there was a significant difference in volatile odor of tuna stored at-60℃when compared to-18℃.TVC showed no significantly change,and it was below Industry Standard Limits.Therefore,the temperature should be kept stable during processing,transportation and storage of tuna.The best temperature is-60℃.