WEC 31: Faber vs. Curran was a mixed martial arts (MMA) event held by World Extreme Cagefighting (WEC). The event took place on Wednesday, December 12, 2007 at the Hard Rock Hotel and Casino in Las Vegas, Nevada and was aired live on the Versus Network. Future WEC & UFC champion Dominick Cruz was scheduled to make his bantamweight debut against Charlie Valencia at this event, but was later forced from the card and replaced by Ian McCall. The Cruz/Valencia bout was rescheduled for WEC 34 the following June, where Cruz won by unanimous decision.