Abstract: This study cloned the full-length cDNA of UHRF1 (PtUHRF1) from the swimming crab Portunus trituberculatus using rapid amplification of cDNA ends (RACE). The length of PtUHRF1 cDNA was 2849 bp, which contained a 2298 bp open reading frame to encode 765 amino acids. Structure analysis revealed that PtUHRF1 contained several conserved domains, including UBL, PHD, TTD, SRA and RING. Homology analysis revealed that PtUHRF1 exhibited high identity with other species. The expression of PtUHRF1 at mRNA level was detected in all tested tissues with the highest level in testes. PtUHRF1 showed stage-specific expression during embryonic and larval development with the highest expression in fertilized egg. There were significant differences in PtUHRF1 expression at different ovary and testis stages. In ovary, its expression reached the highest value at stage II, and then decreased gradually, while in testis, the highest expression was detected at stage I, and then decreased as testis developed. These results indicated that PtUHRF1 is important in regulating embryonic, larval and gonadal development in the swimming crab, and provided useful reference for further studies on the roles of this gene in growth and development of P. trituberculatus and crustaceans.