Arctostaphylos rainbowensis is a species of manzanita known by the common name Rainbow manzanita. It is endemic to California, where it is known only from northern San Diego and southern Riverside Counties in the Peninsular Ranges. It was named for the community of Rainbow, California, near where it is most common in the chaparral of the lower elevation coastal Santa Ana Mountains, and the only manzanita species throughout most of its range.