Abstract: The tuna is mainly used for processing of raw fish, fish fillets, steaks and a variety of canned fish and other products.A lot of by-product with poor flavor have been produced in this process.Most of them were made into animal feed and have low economic value though they were rich in protein and unsaturated fatty acid.In this study, the effects of lactobacillus fermentation on improvement the flavor of tuna meat were researched.The electronic nose and GC-MS were used to detect the flavor of tuna meat enzyme hydrolysate unfermented and fermented in different time.The results indicated that the content of acetaldehyde in the enzymatic hydrolysate of tuna meat was 11.51%, when the enzyme hydrolysate was fermented by lactobacillus for 72 h, it was under the detection limit, and the content of furan which has low threshold and good flavor was low at 0.68% when the enzyme hydrolysate was unfermented and reached a peak 5.31% of after 48 h fermentation.Our research provided a theoretical basis about how to use of tuna scraps and improve its economic value.