The quake struck one mile north-northeast of Brea and two miles east of La Habra at 3:35 p.m. PT.
Residents in Brea, Fullerton, La Habra and Rowland Heights reported feeling shaking from the quake.
There were no reports of damage or injury.
In March, a 5.1-magnitude earthquake struck La Habra and the surrounding area, causing damage to several homes and buildings.