Abstract: To understand species composition and macro-benthic diversity and to assess health of Rizhao subtidal zone ecosystem, the investigation data collected in May and November 2016 are studied. In total，60 species of macrobenthos were identified, among them 30 species were Annelida， 16 were Crustacea，8 were Mollusca and 6 were other groups.Sigambra bassi, Amphicteis gunneri, Capitella capitata, Yoldia notabilis were recorded as dominant species in spring and Hemigrapsus penscillatus, a species of Lumbrineriiae, Callanssa harmandi, Pista branchia were recorded in autumn. The averages density, biomass, Shannon diversity (H′) and Margalefs species richness index (d) were 96.83 ind./m², 6.21 g/m², 1.45 and 0.40 in spring and 112.63 ind./m², 14.75 g/m², 1.66 and 0.44 in autumn, respectively. Cluster analysis showed that the macrobenthos in Rizhao subtidal zone can be divided into four groups. The ABC curve analysis showed that the four groups were seriously disturbed by human activeties. Results of BVSTEP analysis showed that water temperature, dissolved oxygen (DO), nitrite, oils and arsenic in the sea water were the key environmental factors affecting the macrobenthic community structure. Pearson correlation analysis further showed that depth of water, water temperature, pH, chemical oxygen demand (COD) and copper in the sea water had the most influence on abundance and biomass of macrobenthos. Compared with historical data, the total species, average biomass and average abundance of macrobenthos in the study areas were decreased significantly.