please tell me requirement/elligiblity criteria for master of engg. admission in england for an international student .

Best thing to do is to contact universities offering the course you want to do and discuss with them directly what the entry requirements are for that institution.

I'm doing my second year of mechanical engineering and i'm already researching unis @ which i will be doing my Masters in eng~

The usuall requirement varies between a 2.1 and a 2.2 class hons->tell me where exactly you'r from and i'll tell you the equivalent.

You will also have to prove that your english is sufficiently good enough->tefls etc.