Abstract: Based on the investigation of fish larvae resources by monthly otter trawl surveys in the mangrove of Mao-weihai Bay from July 2012 to June 2013,species composition and abundance and environmental factors,mainlytemperature and salinity and tideswere analyzed.A total number of24 species of fish larvae belonging to 15 familiesand 18 genera were collected during the investigation.The structure of fish community was simple and it was com-posed of mostly offshore wam water species.Pseudogobius jaranicus were the most dominant species in the man-grove of Maoweihai Bay.Accordingto hierarchical clustering,the community structure of fish larvae could be divid-ed into 3 groups.The group I was from December to January;the group II was from Febuary.to March;the groupⅢ was from May to November.The correlationanalysis showed species richness and abundance of Pseudogobius ja-ranicus were significantly related to tidal level(high/low tide)and the abundance of Omobranchus elegans was sig-nificantly related to tide pattems(diumal tide or semidiumal tide).The correlation analysis between communty ofish larvae and environmental factors showed that only abundance of fish larvae was significantly and positively cor-related to the temperature.