Aroma is an important evaluation index of freshness and flavor of aquatic products, which has an essential influence on product quality rating and consumer orientation. The studies showed that the types and contents of volatile compounds were the main reasons for the difference in aroma of aquatic products, and different aquatic products, freshness and processing methods all affected the final aroma. Aroma composition of aquatic product is complex, and accurate analysis of volatile flavor substances is the key to research its characteristic aroma. The sensory evaluation and instrumental analysis techniques for aroma analysis of aquatic products were reviewed and the characteristic aroma substances of different aquatic products were summarized. The characteristics of more than 300 kinds of volatile components (including aldehydes, ketones, alcohols, acids, and sulfur-containing compounds, etc.) found in aquatic products were discussed. The molecular sensory science was employed to analyze key aroma of fresh aquatic products and processed aquatic products such as thermal treatment and fermentation processing, and the results showed that the aldehydes, ketones and alcohol, etc gives fresh aquatic products unique fragrance. However, the key aroma substances were significant differences in aquatic products with different processing methods. In order to systematically study the chemical essence and flavor formation mechanism of inherent aroma aquatic products, the metabolic pathways of key aroma substances in aquatic products should be revealed in molecular level. Finally, the interaction between aquatic product matrix and aroma substances and the elimination mechanism of fishy smell and peculiar smell were discussed. It was suggested that the combination of modern instrument analysis method and molecular sensory science, and the in-depth discussion of the formation pathway and aroma release mechanism of aquatic products would be the keypoint of aroma research of aquatic products in the future.