The demonstrators are concerned about issues such as immigration and healthcare and want lawmakers to meet with constituents.
The events were held as part of a national week of action while Congress is out of session and members are back in their districts.
Many of the Southern California protesters said they wanted to speak with their congressmen about preserving the Affordable Care Act.
Protesters showed up at the offices of Republican congressmen Dana Rohrabacher in Newport Beach, Steve Knight in Santa Clarita and Ed Royce in Fullerton.
Eyewitness News reached out to Rohrabacher, Knight and Royce for comment, but they were not available.
For a full report on the protest, see the video above.