Loma Mar (Spanish for "Sea Hill") is a census-designated place (CDP) in San Mateo County, California.

[2] It is near San Mateo County Memorial Park on Pescadero Creek Road and is in area code 650.

Loma Mar is between the towns of Pescadero and La Honda, situated in the Santa Cruz Mountains in the western part of the San Francisco Peninsula.

According to the United States Census Bureau, the CDP covers an area of 1.7 square miles (4.5 km2), all of it land.

There were 67 housing units at an average density of 38.6 per square mile (14.9/km2), of which 31 (57.4%) were owner-occupied, and 23 (42.6%) were occupied by renters.