Glen Mills is an unincorporated community in Concord Township, Delaware County, Pennsylvania, United States, located approximately 27 miles west of Philadelphia.

The area around Glen Mills was part of the original land grant given to William Penn in 1681.

A Wild West themed restaurant/roadside attraction known as The Longhorn Ranch operated in Glen Mills during the 1960s.

A Glen Mills resident, pilot Michael R. Horrocks, died in the September 11, 2001 attacks.

[7] The Glen Mills ZIP Code, 19342, is unusual in the numerous geographic boundaries it crosses.