Reynolds, 39, and Lively, 28, were dressed to the nines at the Deadpool fan event at the AMC Empire Theatre in New York City on Monday.
The married couple made their first appearance together as parents since welcoming 13-month-old daughter James in January 2015. The pair married in September 2012.
Preserve guru Lively looked stunning in Chanel Houte Couture while her husband was dapper in a white polka dot dress shirt and navy suit.
Hundreds of Deadpool fans dressed up as the wisecracking assassin and even took part in a beauty pageant!
Lively has been Reynolds' biggest supporter throughout the press tour most recently posing for a playful (and handsy!) photo op in front of the film's promotional poster.
Also in January, the Gossip Girl alum attended a surprise advance screening of the latest X-Men installment.
And in December, the father of one shared a photo of an adorable handmade Deadpool doll his wife got him.
Deadpool hits theaters Feb. 12.