Cruz, who dated Cruise from 2001 to 2004, declined to offer details of the meeting but praised Suri as a special baby.
"She's really beautiful. She's one of the most beautiful babies I've ever seen," the 32-year-old actress said. Cruz was in London Thursday night to attend the British premiere of her new film, "Volver."
Suri, the daughter of Cruise, 44, and his fiancée, Katie Holmes, 27, was born in Los Angeles on April 18. She has yet to be seen in public.
However, actresses Jada Pinkett Smith and Leah Remini have reported seeing Suri in separate visits to the Cruise-Holmes mansion in Los Angeles.
Pinkett Smith has described Suri as "one of the sweetest babies I've ever met in my life," while Remini has said the baby "looks like Tom and Katie, she's just beautiful."
Cruz was photographed earlier this week in St. Tropez, France, partying on the yacht of rap mogul Sean "Diddy" Combs alongside actress-socialite Paris Hilton and Sarah Ferguson, the Duchess of York.
"It was fun and crazy," Cruz said. "I don't party too much, but that night I was on holiday. I've known Diddy for a while since we worked together on a campaign and became friends."