The Oprah effect is an expression referring to the effect that an appearance on The Oprah Winfrey Show, or an endorsement by Oprah Winfrey, can have on a business. Because the show reaches millions of viewers each week, a recommendation from Oprah can have a significant and often unexpected influence for a new or struggling business.

People and companies lucky enough to appeal to Oprah can find overnight success after being promoted on her show. An endorsement from Oprah can suddenly turn a small, unprofitable business into a multimillion-dollar company.