Monday's program was the agency's first buyback since 2009.
Officials said they offered $50 gift cards for gun parts and non-working guns, $100 for handguns, shotguns and rifles, and up to $200 for assault weapons.
The Los Angeles Times said the sheriff's department collected 386 weapons, including 193 rifles, 144 handguns and 22 assault rifles.
The program follows a Los Angeles Police Department's gun buyback in late December. Both programs were a result of increased concern about gun safety following the Dec. 14 massacre of 20 children and six adults at Sandy Hook Elementary School in Newtown, Conn.
The Sheriff's Department said they will destroy the guns at its annual weapons meltdown in July, and the salvaged steel will be reused for rebar, road construction and art installations.