Mantis shrimp (Oratosquilla oratoria), the main catches of stow net fishing vessel in Zhangpu, Fujian Province, were followed and sampled monthly from August 2022 to April 2023. A total of 368 samples were used to determine the body length and body mass, to characterize the feeding intensity and female ovarian development, and to calculate the ratio of males to females in the catch, in order to analyze the fishery biology of O.oratoria. The results showed that the ratio of female to male was 1∶1.115 in the catch of O.oratoria, the dominant body length group was 110-130 mm, the dominant body mass advantage group was 15.0-25.0 g,and there was no significant difference in average body length and average body mass between male and female samples. The relationship between body length and body mass was W = 2.140×10^-5L^2.882 (R² =0.946, n=368). The gonadal maturity of female O.oratoria was between stage Ⅰ-Ⅲ, and stage III individuals mainly appeared from February to April. The average feeding grade of O.oratoria was 1.44, of which grade 1 was the most. The average annual condition factor index of O.oratoria was 1.226, and the male was slightly larger than the female.