Objective: To analyze the effects of biological deodorization by microbial fermentation of scallop on the main volatile flavor components of scallop， and to clarify the mechanism of biological deodorization. Method: Combined with ozone pretreatment， respectively adopt single bacteria (Lactobacillus RP38) and mixed bacteria (Lactobacillus RP38 + Saccharomyces cerevisiae JJ4) to biological trends of scallops. The volatile flavor components were analyzed by headspace solid phase microextraction coupled with gas chromatography-mass spectrometry(HS-SPME-GC- MS)， and identified by multivariate statistical methods and ROAV(relative odor activity value). Results: Ozone treatment could reduce the total number of bacterial colonies by about 1 order of magnitude and 48.4% TVB-N， which had little effect on flavor. The different flavor of scallop before and after biological deodorization was constructed by aldehydes and alcohols. The low saturated aldehydes and alkynes were mainly degraded by biological fermentation， and unsaturated fatty aldehydes， alcohols and ketones were increased. Principal component analysis showed that the characteristic products of single fermentation were 1-heptanol， α-bisabolol， (2E)-2-nonenal， etc.， while the characteristic products of mixed fermentation were 1-pentanol， benzaldehyde， (2E)-2-octenal and lyral， etc. The mixed fermentation could produce more abundant and diverse volatile flavor components. ROAV analysis showed that the active components of volatile flavor of scallop were octanal， (2E) -2-nonanal， nonanal， 1-nonanol， heptanal and capraldehyde. 1-Heptanol， 2-nonanone， (2Z) -2-heptenal and (2E)-2-octenal were the important flavor modifying components after biological deodorization. Conclusion: The ozone treatment could maintain the freshness of scallop. Ozone treatment could keep scallop fresh. Biological deodorization mainly through degradation of low-grade aldehydes with odor characteristics， and the fresh unsaturated aldehydes and alcohols were produced. The mixed fermentation could achieve the synergistic deodorization effect.