For starters, are you sure its a fossil? And could you give a age/formation and location description. Also, it would help if I could see some pictures from different angles. You might get a better response with a little more info, and you should try posting it in the Fossil ID section of the forum.

From what I can see, I would guess fish, but Im far from positive. Good luck!

CBK

Yeah definitely fish and likely modern. Looks like some sort of parrot fish type species eating crustations and mollusks.

It's not a fossil, it is cat fish head. I'm 100% sure.