Mill Creek is a mountain stream in the Angeles National Forest of Los Angeles County, California, and a major tributary of Big Tujunga Creek. It flows in a southwesterly direction for about from near Mill Creek Summit in the San Gabriel Mountains to join Big Tujunga Creek near the village of Hidden Springs. The Mill Creek valley provides a major part of the route of Angeles Forest Highway (County Road N3). Mill Creek Summit, , is the highest point along the road.
The named tributaries of Mill Creek, from upstream to downstream, are Monte Cristo Creek, Middle Fork Mill Creek, and North Fork Mill Creek.