Hello,
I and my wife both travelled to US on 1st April 2006. I was on L1 Visa. SSN tax, State, etc taxes are deducted from my salary paycheck. We left USA on 26 Feb 2008. I need to file a 2008 tax return and confused on resident alien or non resident alien. Below are the stay periods in USA.

Year 2006 - 300 days
Year 2007 – 365 days
Year 2008 – 56 days

For filing 2008 tax return what will be my status?

You will file dual status tax return-- resident up to Feb 26, 2008 and non-resident after that date.

Agreed. If you BOTH worked, you each need to file your own dual-status return. If only you worked, you will file and can claim your wife as a dependent.

Note that you will NOT be allowed to claim the standard deduction, but rather MUST itemize.

This type of tax return is NOT FOR AMATEURS! You need to get professional help.

For information on dual status tax years, see page 33 of IRS Publication 519. http://www.irs.gov/pub/irs-pdf/p519.pdf