Tropomyosin (TM) is a major allergen in aquatic products. The aim of this study was to analyze the allergenicity of TM from different aquatic products based on conformational and linear epitopes. Structural and allergenicity analyses of TM were conducted using intrinsic fluorescence, UV absorption spectra, circular dichroism, and animal experiments. Epitope mapping was performed through bioinformatics software and a one-bead, one-compound (OBOC) peptide library screening approach. The results showed that the structures of TMs from different aquatic products are similar. Cross-reactivity was observed among TMs from different aquatic products, with fish-TM showing lower cross-reactivity compared with other TMs. Additionally, 13, 14, 11, 13, and 12 linear epitopes, along with 2, 2, 1, 2, and 3 conformational epitopes, were identified for shrimp-TM, crab-TM, fish-TM, oyster-TM, and clam-TM, respectively. Overall, these findings provide a basis for elucidating the epitope localization and allergenicity relationship of TMs from different aquatic products.