I am a legal resident living abroad. Will I lose my Green Card if I file a tax return that shows that al my income is earned in another country?

I believe that you are confusing the payment of taxes with maintenance of your green card. DHS knows how long you have been out of the country through its record-keeping of your record of travels and through your passport. Stays outside the US for extended periods of time may subject you to loss of the green card regardless of whether you file US taxes or not. As a US permanent resident, you are obligated to file taxes on your worldwide income. In my opinion, the most damaging aspect of filing taxes immigration wise would be to claim a foreign income exemption as you would be stating on the tax return that you consider yourself a nonresident of this country. Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.