Alarcon pleaded not guilty to the 18 counts. Those charges include perjury and voter fraud, among other allegations.
His wife, Flora Montes De Oca Alarcon, pleaded not guilty six similar charges.
It was not immediately clear how much prison time they would face if convicted.
Alarcon has been under investigation since allegations were made last year that he didn't live in the Panorama City home he used as a voting address.
Alarcon and his wife said nothing during the brief hearing Wednesday in Superior Court but he had denied breaking any laws.
Alarcon, who represents portions of the San Fernando Valley, says he and his family moved last October to Sun Valley after a man broke in and vandalized the Panorama City home. Sun Valley is in a neighboring district.
"The charges by the district attorney are baseless," Alarcon told reporters after the indictment. "My wife and I are innocent. The house located at 14451 Nordhoff Street in Panorama City has been my residence since November of 2006 and that of my family since my marriage to Flora in August of 2007. We recognize this is going to be a long process, and I would only ask that people are patient with the judicial proceeding and not rush to judgment."
Alarcon indicated he was going to stay in his council seat. He can't be removed unless he's convicted of perjury, and then it's automatic. But he could be suspended if the council decides to do so.
Alarcon, who has spent a lot of time in the state senate, state assembly and on the city council, now faces the disgrace of the charges and a long, drawn-out, embarrassing trial.
The Associated Press and City News Service contributed to this report.