If you look into the statistics, you can see most of the engineers study MBA after completion of their graduation.
There's no problem whether you're from science or commerce background . The minimum eligibility criteria is you need to score atleast 50% - 55% (varies in different colleges) in your graduation.

Hello

Yes, you can definitely do MBA in Finance even if your education background is in Science Stream. There are students whose edu. background is engineer, IT, BSC, etcand have done MBA(Financial Management and Business Laws) and got placed.

I hope it will help you
Good luck.....