Hello,
I am on F1 status since August 2004... I have been filing 1040NR-EZ for last 4 years... But one of my friends told me that I can file 1040 after 3 years. So is it okay to file 1040 instead of 1040NR-EZ or 1040NR?

On F1/OPT you are exempt from residency for 5-years. You must file non-resident tax return Form 1040NR or 1040NR-EZ and Form 8843.

On your F1 income you will get deduction based on tax treaty between the U.S. and your country.
Read: Your U.S. Tax Return: U.S. Tax Filing Requirements for Non-Residents

MukatA,

Thank you very much for clarification... I thought exempt from residency is for 3 years.

-vishwas

Read IRS Publication 519: Tax for Aliens