The Wrinkle in Time actresses enjoyed the theme park with co-star Storm Reid after attending a surprise screening of the film at Sunset Showcase Theater in Disney California Adventure Park.
Kaling, Winfrey and Witherspoon play Mrs. Who, Mrs. Which and Mrs. Whatsit in A Wrinkle in Time, which is based on the Madeleine L'Engle book of the same name. Reid stars as young protagonist Meg Murray.
"#WrinkleinTime's Mrs's and Meg surprised fans @disneyland," Disney Studios captioned a slideshow on its official Instagram account.
Kaling shared a series of posts on her own account, including a Boomerang video of herself and Witherspoon wearing black and silver Minnie Mouse ears.
"@reesewitherspoon! Boomerang by my love @mollyrstern," she wrote, tagging makeup artist Molly R. Stern.
The Disneyland trip marked Kaling's first public outing since welcoming her first child, daughter Katherine, in December. The new mom shared a makeup-free selfie during a girls weekend with a friend this month.
"No makeup no filter mom night out with @juliaspowellart," she wrote.
A Wrinkle in Time opens in theaters March 9. The movie is directed by Ava DuVernay, who shared details about the film's soundtrack this week. The album will include original songs from Sade, Sia and Demi Lovato.