To enhance the quality and flavor of the byproduct skirt of Argopecten irradians， Lactobacillus plantarum subsp. Plantarum Lp-4 (Lp-4 group)， Lactobacillus casei Y5-2b (Y5-2b group)， Kluyveromyces marxianus FCC2181 (FCC2181 group)， and Pichia kluyveri F29-3-5 (F29-3-5 group) were used to carry out single-organism fermentation of irradians skirts， determined the changes of flavor substances in the fermentation broths of the inoculation of different fermentation strains， and analyzed the effects of free amino acids and free fatty acids as flavor precursors on the flavor substances in the context of the changes of flavor substances and the antioxidant capacity of the strains. The results showed that both lactic acid bacteria and yeast strains grew well during the fermentation process of the scallop skirt cooking liquid. The pH value of the fermentation liquid decreased significantly， and the fermentation promoted the formation of the skirt fermentation liquid flavor. Specifically， the viable cell counts of the Lp-4 group， Y5-2b group， FCC2181 group， and F29-3-5 group increased from 7.04， 6.99， 5.93， 6.07 lg(CFU/mL) to 8.49， 8.17， 8.01， 8.18 lg(CFU/mL)， respectively. After 36 hours of fermentation， the Y5-2b group had the lowest pH of 3.33， while the FCC2181 group had the highest pH of 5.52. The FCC2181 group had the highest content of flavor compounds， while the Lp-4 group had the least. Compared to other groups， the FCC2181 and F29-3-5 groups produced more alcohols， while the Lp-4 and Y5-2b groups produced more acids. The fermentation groups had more esters than the control group， and aldehydes were relatively high in all groups. At 36 hours of fermentation， the Y5-2b group had the lowest thiobarbituric acid value of 0.27 mg MDA/kg， corresponding to a lower content of free fatty acids， indicating a smaller degree of oxidation. In summary， fermenting the bay scallop skirt with the four different strains resulted in good flavor and quality. Lactic acid bacteria fermentation yielded acidity， while yeast fermentation accumulated more alcohol flavor compounds. The results of this study provide a scientific basis for further optimization of fermentation strains for scallop skirt.