子宫外膜（英语：perimetrium）或称子宫浆膜（serous coat of uterus）是指子宫的外部浆膜，相当于腹部的腹膜。它由腹膜脏层生长而出。

The perimetrium (or serous coat of uterus) is the outer serosa layer of the uterus, equivalent to peritoneum. It is embrionically derived from visceral peritoneum. Perimetrium consists of superficial mesothelium, and a thin layer of loose connective tissue beneath it. Posterior surface of the uterus is completely covered by the perimetrium, but anterior surface only partially.