Kathleen M. Dumais (born July 5, 1958) is an American politician who represented the 15th District of the Maryland House of Delegates, encompassing the western and northern portions of Montgomery County.

Born in La Jolla, California, Dumais grew up in Maryland and eventually pursued a degree at the University of Maryland School of Law.

As an attorney, she specialized in family and juvenile law and had a career-long interest in education, at one point working as a teacher in Montgomery County Public Schools.

In 2002, Dumais was elected to the House of Delegates from District 15, which includes Potomac, Germantown, and a large swath of rural northern Montgomery County.

In November 2021, Dumais resigned from the House of Delegates after being appointed to serve on the Montgomery County Circuit Court bench by Governor Larry Hogan.