We're told the famous Russian-German DJ and the former Miss Universe were cuddling in the artist area during Ariana Grande's set at Coachella. Check out the vid ... it appears Zedd had his arms around Olivia as Grande performed "God is a woman."

Witnesses tell us they were together for the whole set. His arms were around her as they swayed together. She would lean her head back on his chest ... the universal code for "I'm into you."

And, get this ... Zedd had a performance scheduled a few hours before Ariana's. When he went onstage ... guess who was backstage? Yup ... Olivia and her hot friends. But, here's what else is interesting ... this fling seems to come just days after Olivia was spotted with another star ... NHL's Aaron Varos.

Olivia and the New York Rangers star were on a double date just last week at Soho Hollywood. They were hanging with her best friend Cara Santana and Jesse Metcalfe. So, ya gotta wonder ... was Olivia's date with Varos a one-off and is Zedd more her jam???

Whatever the case ... one thing that seems certain -- Danny Amendola's in her rear-view mirror.