The Team GB star and double Olympic gold medallist told Sky News that he and his wife Tania welcomed the new arrivals on Friday (August 24).
"My wife gave birth to two little beautiful girls. It is very exciting," he said.
When asked if he would be joining his wife at her bedside, Farah - who is in Birmingham preparing for tomorrow's Aviva Grand Prix - said: "No, no, no. I've got a race tomorrow, haven't I?"
The 5,000m and 10,000m Olympic champion is rumoured to have signed up as a guest mentor for the current series of The X Factor. He will also star in a series of adverts for Virgin Media alongside Usain Bolt.
Following his London 2012 victories, which he dedicated to his then unborn daughters, Farah is hoping to break Steve Ovett's outdoor record of eight minutes, 13.51 seconds for the two-mile distance at tomorrow's Grand Prix.
Photo gallery - Team GB's gold medal winners:
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