The resolution "authorizes a referendum and accompanying educational information be sent to the members requesting their authorization for the National Board to call a strike" if negotiations fail.
If 75 percent of SAG's 120,000 members vote in favor of a labor action, it would then be left to the national negotiating committee to call the strike if it deems it necessary.
"We hope mediation will help move this process forward. This action by the board demonstrates our commitment to bargain with the strength of our unified membership behind us," said Screen Actors Guild National President Alan Rosenberg in a statement.
SAG's chief negotiator Doug Allen said the union's goal remains securing a good contract without a strike.
Actors in prime-time television and movies have been working under the terms of a contract that expired June 30, hoping to avoid a repeat of the 100-day writers strike that ended in February. That strike cost the Los Angeles area economy an estimated $2.5 billion.
The studios, represented by the Alliance of Motion Picture and Television Producers, said recently that, considering the current economic turmoil, it is "unrealistic for SAG negotiators now to expect even better terms during this grim financial climate."
Phone calls seeking comment on Sunday from the alliance were not immediately returned.
The actors guild wants union coverage of all shows made for the Internet, and residual payments for actors on made-for-Internet shows. It also demands protections for actors during work stoppages.
The alliance has stuck by a final offer it made June 30, which it said mirrored deals accepted by directors, a smaller actors union called the American Federation of Television and Radio Artists, and writers following their strike.
