The natural resource of Psammotaea virescens is gradually disappeared in recent year. The present study was conducted on the anatomy of Psammotaea virescens and their environmental condition for the further research. The specimens were collected from Lin-bien, Pintung Shien and were dissected to draw their inner shell, digestive and muscular system, visceral mass and hinge plate. The hinge teeth formula of Psammotaea virescens is as follow: 3a,3b/2,4b.The ratios of shell height and shell width to shell length were 0.568 ± 0.028 and 0.339 ± 0.0.021 and were significantly higher than that of Sanguinolaria diphos. When the typhoon season and flood were encountered, the salinity was changed abruptly and even down to 0 ppt for three weeks. It’s a serious stress to these Psammotaea virescens.