丝膜菌科（Cortinariaceae）是担子菌门下伞菌目的一科。具有丝状保护膜保护菌褶及暗色孢印为本科主要特征，大多有毒或不宜食用。

The Cortinariaceae are a large family of gilled mushrooms found worldwide, containing over 2100 species. The family takes its name from its largest genus, the varied species of the genus Cortinarius. Many genera formerly in the Corinariaceae have been placed in various other families, including Hymenogastraceae, Inocybaceae and Bolbitiaceae.