The measure was later revised to 4.0, the Ventura County Star reported.
There were no immediate reports of significant injuries or structural damage, FOX 11 of Los Angeles reported.
The quake struck around 5:44 p.m. PT about four miles northwest of Santa Paula, with an estimated depth of about 16 miles, the U.S. Geological Survey said, according to FOX 11.
A similar-sized quake struck the same area Feb. 10, the Star reported.
Both quakes were considered "very deep" for the Southern California region, seismologist Dr. Lucy Jones wrote in a Twitter message.
Saturday’s shaking was felt as far south as Long Beach and as far west as Santa Barbara, the FOX 11 report said.