贻贝科（学名：Mytilidae），也叫蜐、海虹、青口，，干制品则被称作淡菜，是一种双壳类软体动物，壳黑褐色，肉米黄色至橘红色不等，生活在海滨岩石上。

本科现时有52个属，分别如下：

The Mytilidae are a family of small to large saltwater mussels, marine bivalve mollusks in the order Mytiloida. One of the genera, Limnoperna are inhabits in brackish or freshwater environments. The order has only this one family which contains some 52 genera.