My fiance was deported from UK for overstaying his visa.I'm a EU citizen studying In Uk?

He has been deported for violating immigration laws/visa regulations and he is NOT returning. You are not a UK citizen, and you cannot do diddly about it. Even if you go to Mexico and marry him, he is not returning to UK. And if you are EU citizen, he cannot get into any EU country either. Countries share info. Even after completing his bar to reentry, chances are he is never getting a visa anywhere because of his record of lawbreaking.