To improve the utilization rate of Stichopus japonisus gonads and to prepare seafood flavor seasoning with better flavor.The enzymatic hydrolysateof gonads was subjected to a Maillard reaction with the addition of D-xylose and L-cysteine, and the changes of taste and odor of gonad enzymatic hydrolysates were analyzed by combining low molecular mass flavor intermediates, browning degree, free amino acids, flavoring nucleotides and volatile substances. The results showed that the content of umami and sweet free amino acids increased significantly and the proportion of bitter free amino acids decreased after the Maillard reaction； AMP was the main flavor-presenting nucleotide in enzymatic hydrolysates of Stichopus japonisus, and the content decreased significantly after the reaction； the types and amounts of key flavor compounds increased. The aldehydes were the main volatile flavor components, benzaldehyde was the most different substance before and after the reaction； pyrazine, thiophene and 2-ethylfuran were the characteristic flavor substances formed by the Maillard reaction.The gonadal enzymatic hydrolysate/D -xylose/L-cysteine Maillard reaction products have good flavor and can be used as a reference for the development of high quality flavoring bases and functional foods.