"They are married," said an LA spokesman for the 43-year-old actor, best known for playing superspy James Bond in the film franchise. He provided no more details.
People magazine said the couple, who were first cited as a couple last autumn, married in a quiet ceremony in New York on Wednesday.
Weisz, 41, won an Oscar for her role in "The Constant Gardener".
The newlyweds play husband and wife in the upcoming "Dream House", due out in the United States in September.