Manny Pacquiao just got hit with a $10 million lawsuit!

Manny Pacquiao just got hit with a $10 million lawsuit -- but not for breaking anyone's eye socket ... rather, because he allegedly screwed over a company that hired him to record music.

RBM Group International filed a lawsuit today against Manny in L.A. County Superior Court -- alleging the pound-for-pound boxing champ signed a contract in 2009 in which he promised to record 12 songs ... but never did.

In the docs, RBM claims they wrote Pacquiao a $40,000 check in October of '09 -- which he deposited -- in return for the first two songs ... but the boxer has refused to record the music.

RBM claims they're out of pocket $200,000 ... and they've lost profits in the amount of $10 mil.

Calls to Manny's people have not been returned.

UPDATE: If you've never heard Manny sing ... check out the video.