牛角瓜属（学名：Calotropis）是萝藦科下的一个属，为直立灌木或小乔木植物。该属共有6种，分布于热带亚洲和非洲。

Calotropis is a genus of flowering plants in the dogbane family, Apocynaceae, first described as a genus in 1810. It is native to southern Asia and North Africa.

They are commonly known as milkweeds because of the latex they produce. Calotropis species are considered common weeds in some parts of the world. The flowers are fragrant and are often used in making floral tassels in some mainland Southeast Asian cultures. Fibers of these plants are called madar or mader. Calotropis species are usually found in abandoned farmland.