Phacelia breweri is a species of phacelia known by the common name Brewer's phacelia. It is endemic to California, where it grows in the mountain ranges in and around the San Francisco Bay Area. It is a member of the flora in chaparral, woodland, and other local habitat. It is a branching annual herb spreading or growing upright to a maximum height near 45 centimeters. It is glandular and coated in soft and coarse hairs. The lance-shaped or oval leaves are up to 4 centimeters long, the lower ones lobed. The hairy inflorescence is a crowded, one-sided, curving or coiling cyme of many bell-shaped flowers. Each flower is about half a centimeter wide and light blue in color.