The 29-year-old singer attended the Los Angeles premiere of Turner's movie Dark Phoenix at the TCL Chinese Theatre in Hollywood.
Jonas put an arm around Turner's waist as they posed for photos together.
Turner wore a strapless dress with stripes and floral embroidery, while Jonas sported a striped shirt and black suit.
Turner, who married Jonas in May, shared a close-up photo on Instagram of her look for the event. The 23-year-old actress was named the face of Wella hair products in June 2017.
"Dark Phoenix premiere @wellahairusa," she captioned the post.
Turner's co-stars James McAvoy, Michael Fassbender, Jennifer Lawrence, Nicholas Hoult and Jessica Chastain also attended the premiere.
Lawrence, who previously dated Hoult, discussed her fiancé, Cooke Maroney, and their engagement on the red carpet.
"He's just the best person I've ever met in my whole life," she told Entertainment Tonight. "It was a very, very easy decision."
Turner plays the X-Men mutant Jean Grey in Dark Phoenix, which opens in theaters Friday. She also starred on the HBO series Game of Thrones, and discussed her character Sansa Stark's ending in an interview published last week.
