The approval, at a CIF meeting in Long Beach, was passed by a vote of 61 in favor and 26 against, with two abstentions.
Following the approval, the state federation - which governs interscholastic sports in California - is expected to take it up next month with a goal of making it an official sport in the nation's most populous state for the 2023-24 school year.
The number of girls playing flag football in U.S. high schools doubled to 11,000 in the decade leading up to 2018-19, according to the National Federation of State High School Associations.
Flag football already is a sanctioned high school girls sport in states including Alabama and Nevada. And it was added as a collegiate sport by the National Association of Intercollegiate Athletics, with colleges in Florida, Georgia, Kansas and elsewhere fielding teams.
While girls are allowed to play tackle football on high school teams in California, few do. Flag football allows them to experience the sport in a way "that has all the knowledge, skills, and ability and the strategy of traditional football without some of the more violent parts of it," said Paula Hart Rodas, president-elect of the CIF Southern Section's council who previously coached Lawndale High School's flag team.
In flag football, no one gets tackled. A play ends when an opposing player pulls off the flag of a ball-carrier. It also is far cheaper than tackle football since no helmets or pads are needed.
The NFL sees flag football as a way to encourage its female fans. The Los Angeles Rams and Los Angeles Chargers started a pilot high school league during the last school year, giving many girls a first shot at playing.
Chase Hartman, the Chargers' former community relations manager, said more than 70 schools filled out interest forms for the new pilot league. The NFL teams selected eight schools to start and provided uniforms and gear.
"The response was quite frankly more than we were prepared for," he said.
The Associated Press contributed to this report.