Based on the macrobenthic samples collected by four seasonal cruises from August 2009 to June 2010 from 13 stations in northern Yellow Sea around Zhangzidao Island, the species number, abundance, biomass, biodiversity, and secondary production of macrobenthos from the research area were studied. The results show that 211 species were found, the mean abundance was 699.415 ind./m2, the mean biomass was 98.927 g/m2; the species numbers in different seasons were: spring (121)> autumn (118)> winter (89)> summer (87), the mean abundances in different seasons were spring (794.58 ind./m2)> autumn (766.92 ind./m2)> summer (674.62 ind./m2)> winter (561.54 ind./m2), the mean biomasses in different seasons were spring (180.271 g/m2)> summer (107.121 g/m2)>autumn (70.824 g/m2)> winter (37.493 g/m2); the indices of macrobenthic biodiversity were not much different in spring, summer and autumn, those in winter was the lowest; the mean Shannon-Wiener index was 2.976, the mean species richness index was 4.135 and the mean evenness index was 0.707; the seasonal variations of biomass and species number were obvious, they were higher in spring than in winter; the mean secondary production of macrobenthos was15.335g (AFDW) / (m2 ? a), and the mean P / B value was 1.239.