Justin Bieber Coachella Rehearsal Caught on Camera, See the Sneak Peek

Justin Bieber's already in the desert prepping for Coachella ... and some of his rehearsal was caught on camera.

TikTok users are posting videos that seem to show Biebs practicing for his big headlining set this weekend. You can't see much ... but it sounds like you can hear the pop star singing along to his backing tracks.

**Potential Coachella Spoilers below**

In one clip, JB is running through hits like "Sorry" and "Where Are Ü Now" -- which could open things up for possible cameos by Diplo and Skrillex.

And in a second clip ... Justin's heard practicing "YUKON," the second single off his recent album, "SWAG."

Another video shows a fan filming their reaction to hearing the rehearsal ... naming each song as the singer ran through them.

Of the ones caught on camera, you can hear major throwbacks like "Baby," "Favorite Girl," "One Less Lonely Girl" and "All That Matters."

That clip also teases covers of "With You" by Chris Brown and "So Sick" by Ne-Yo -- two songs JB had covered on YouTube as a child.

Bieber's been gearing up to take the stage in Indio, California by playing a couple of intimate shows in L.A. recently -- where he reportedly only played songs from "SWAG" and "SWAG II."