The Instagram mutiny is underway ... with a bunch of celebs already vowing to NEVER use the photo-sharing service again after the company announced a HUGE change in policy.
The statement pissed off tons of users -- famous and non-famous -- including Kate Walsh and Tiffani Thiessen .. who tweeted, "Really sad to have to end my luv 4 @instagram. Will be deleting my account due 2 their ridiculous new terms."
And there's more ... "Dancing with the Stars" pro Cheryl Burke is also abandoning ship ... tweeting, "Can't believe Instagrams new policy! They r allowed 2 use ALL of ur images in advertising. Will be erasing my account shortly."