The invention provides a method for detecting marine products of the same origin. The method comprises the following steps: designing a specific primer by utilizing a CO1 sequence of cytochrome oxidase genes in mitochondrial genes of a group of marine products of the origin, performing PCR amplification on the different extracted marine products, and generating nucleotide sequences of different PCR fragments; comparing different gene sequences with the CO1 gene sequence of the marine products of the origin, performing biological analysis, thereby determining the authenticity of the products. A rapid, accurate and sensitive authentication method is established for protecting the geographical indication products. According to collection and amplification comparison of a group of conserved genes in aquatic products, molecular bar codes are marked on the geographical indication aquatic products, so that the origin is identified, the local fishery resources are protected, and the competitiveness and popularity of local fishery are improved.