A　microwave-assisted　extraction　used　to　extract　trace　triorganotin　from　aquatic　organisms　and　a　sensitive　analytical　method　for　the　determination　of　ultratrace　triorganotin　(namely　trimethyltin,　triethyltin,　tripropyltin　and　tributyltin)　with　capillary　electrophoresis-inductively　coupled　plasma　mass　spectrometry　were　firstly　described　in　this　study.　The　extraction　method　is　simple,　effective　and　can　be　used　to　extract　trace　triorganotin　in　aquatic　organisms　within　several　min.　The　analytical　method　has　a　much　lower　detection　limit　of　0　2-0.7　ng　Sn/mL　for　triorganotin　compounds,　and　can　be　used　to　determine　trace　triorganotin　in　aquatic　organisms　directly　without　any　derivatization　and　preconcentranon.　Using　above　methods,　we　have　successfully　determined　trimethyltin,　triethyltin,　tripropyltin　and　tributyltin　in　dried　Mya　arenaria　Linnaeus　and　Corbicula　fluminea　within　17　min　with　a　recovery　of　93-104%　and　a　RSD　(relative　standard　deviation,　n　=　6)　of　2-5%.　Our　results　showed　that　dried　M　arenaria　Linnaeus　contained　an　extremely　high　tributyltin　of　5.1　mu　n　Sn/g　dried　weight,　indicating　that　it　may　be　a　good　biomarker　for　the　organotin　pollution　in　ocean　(C)　2009　Elsevier　B.V.　All　rights　reserved.