The estuarine Gobiidae $Tridentiger$ $trigonocephalus$, $Chasmichthys$ $dolichognathus$ and $Favonigobius$ $gymnauchen$ were exposed to various heavy metals. As a measure of acute toxicity, the 96h-$LC_{50}$ in the three species exposed to copper, lead, zinc and chromium was 740-990, 1,660-1,980, 6,180-8,490 and 8,830-11,296 ${mu}gL^{-1}$, respectively. In order of toxicity, the heavy metals were ranked copper>lead>zinc>chromium. The Gobiidae $C.$ $dolichognathus$ was more sensitive to heavy metals than $T.$ $trigonocephalus$ and $F.$ $gymnauchen$.