Q: If I had no job and no income for 2yrs prior to filing for Loan Modification, is it mandatory to file and submit tax returns to qualify for the loan modification?
A: Usually your lender wants to see any kind of information available about your financial situation. Based on the different reasons that apply for a Loan Modification, loss of job and income can be one of them. Explain to the lender why you don't have tax returns. It may even help to actually file returns for those two year, even if there was no income, so you have 'official' documentation.
Best thing to do: Call your lender and ask what kind of financial statements they specifically want to see in your situation. They may be satisfied with just a statement about no income, but again, it depends on the specific rules your lender has.