"I'm marrying up," he said of the star lawyer in an interview with Variety published Sunday.
Clooney, 53, and Alamuddin, 36, reportedly plan to tie the knot in Italy in September. After decades as one of Hollywood's most eligible bachelors, the Monuments Men actor popped the question in April.
The engagement has been a mostly happy time for the couple, who've spent time with family in Italy this summer. But the Daily Mail irked the star with a report he called "completely fabricated" about Alamuddin's mother opposing the marriage on religious grounds, prompting Clooney to set the record straight and defend his future in-laws.
"Every day they write things that aren't true, but every once in a while they write something that is actually dangerous to your family, and it's probably not true," he told Variety of choosing his battles with tabloids. "And that's the one you pick."