In order to investigate the effects of the dominant genus Weissella on the flavor and quality of high-salt liqud-state soy sauce， five salt-tolerant acid-producing bacteria were isolated and screened from high-salt liquid-state moromi， and identified with 16S rDNA sequencing， morphology and physiological and biochemical tests. Strains WS09， WS11 and WS12 were identified as Weissella thailandensis， while strains WS20 and WS23 were identified as Weissella cibaria. The fermentation performance of the strains were investigated， and it was found that the optimal growth temperature of all five strains was 30 ℃， and the strains grew well with a salt concentration of 100 g/L. Among them， the acid-producing capacity， salt-tolerant growth capacity， antibacterial capacity and probiotic properties of Weisseria cibaria WS20 were optimal and could be used for soy sauce fermentation. It was added to the moromi and a 60-day fermentation study was conducted. The physicochemical indicators， organic acid content， the quantity and content of volatile flavor compounds of the soy sauce during fermentation were analyzed， and the sensory evaluation was performed. The fermentation of WS20 addition could promote the accumulation of total acid， ammonia-nitrogen and soluble salt-free solid in soy sauce， which were enhanced by 11.71%， 5.18% and 8.03%， respectively， compared with the control group. Lactic acid and acetic acid were the two organic acids that accounted for the highest percentage in the fermentation of soy sauce， both of which accounted for 70.24% of the total content of seven organic acids， which were 12.50% and 19.69% higher than the control group， respectively. The quantity of volatile flavor compounds was 8 more than the control group， with the content reaching (4 211.64±94.06) μg/L and an increase of 38.92%. The contents of ethyl lactate， ethyl acetate， phenylethanol and 2，3-butanediol were (5.96±0.02)， (236.22±7.81)， (386.17±4.35)， (84.03±1.15) μg/L， which were increased by 4 484.62%， 103.39%， 59.14% and 137.64% compared with those of the control sample， respectively. The aroma， taste， color and body of soy sauce in the test group were better than the control group in sensory evaluation. The screening of Weissella spp. in moromi and its fermentation study in soy sauce laid the foundation for the application of Weissella spp. in soy sauce brewing， and enriched the resources of flavored strains for soy sauce brewing.