We investigated the species composition and utilization patterns of fish larvae and juveniles in the sandy beach surf zone at Si Jiao Island. Between July 2010 to August 2011, fish larvae and juveniles were collected monthly using a seine net (1×4 m, 1 mm mesh-aperture). A total of 1762 fish larvae and juveniles, representing 46 species from 29 families were collected from 8 sites along the island. These included 29 marine species, 14 estuarine species, 2 migration species, and 1 freshwater species. Compared with the surf zone of the south Yangtze estuary and north Hangzhou Bay, which were dominated by migratory and estuarine species, respectively, the sandy beach in Si Jiao island was dominated by marine species, which accounted for 71.68 The standard length of the majority (87.05%) of. Postflexion and juvenile individuals accounted for 24.57% and 68.27% of the total catch, respectively. In terms of abundance, Collichthys lucidus andwere the 10 most dominant species. The CPUE of fish larvae and juveniles was higher in spring and summer and lower in autumn and winter. The CPUE peaked in May, at which time the majority of the catch (86.7%) consisted of . The highest species richness was observed in August, 2010. A Person Correlation analysis (2-tailed) revealed a high species richness and water temperature (<0.05). The spatial variation in CPUE and species richness suggested that fish larvae and juveniles preferred inhabiting protected sandy beaches (St.2, St.5, St.7) rather than open sandy beaches (St.4, St.8), likely due to the low wave action and calm environment.Stations 5 and 7 contributed the most to species richness and had the highest CPUE, respectively. Based on the monthly changes in standard length of the 10 most dominant species, the habitat use patterns of the 10 species could be divided into 3 types: increased in size monthly, suggesting they used the sandy beach surf zone as a nursery area. In contrast, there was little change in the standard lengthPlatycephalus indicus were only observed in the surf zone in a single month, suggesting these species use of the zone is restricted to a single or limited development stage. Our data suggest that a number of fish species, including some commercially exploited species, use the sandy beach surf zone as a shelter and/or nursery ground during their early developmental stages (primarily as juveniles and during postflexion).