"I am a green card holder married to a illegal immigrant. I applied for my citizenship and I put my wife on my files but my taxes indicate that I am single. They sent me back the papers asking for her taxes return. Do they will deny my petition because I said I am married and my wife is illegal? My wife have cancer and its currently under treatment of radiation and Chemotherapy. We also have a 6 years old child.

Thanks for your help.

There are several issues here.

First of all, what do you mean "my taxes indicate that I am single"? As long as you were married on December 31 of a year, you can NEVER file as single on your taxes for that tax year. Someone who is married can file as Married Filing Jointly or Married Filing Separately (or in rare cases Head of Household). This has nothing to do with anybody's immigration status or anything. It's just wrong tax filing. If you filed your taxes wrong, you need to fix it, regardless of whether you are applying for naturalization.

They will not deny your naturalization because of your wife's immigration status.

There are several issues here.

First of all, what do you mean "my taxes indicate that I am single"? As long as you were married on December 31 of a year, you can NEVER file as single on your taxes for that tax year. Someone who is married can file as Married Filing Jointly or Married Filing Separately (or in rare cases Head of Household). This has nothing to do with anybody's immigration status or anything. It's just wrong tax filing. If you filed your taxes wrong, you need to fix it, regardless of whether you are applying for naturalization.

They will not deny your naturalization because of your wife's immigration status.

The agency that helped me with my taxes said that I could not include my wife in my taxes because she has not social security.

What you mean she has no social security number. All people listed as dependents need a unique identification. You would have to apply for an ITIN number for her. Its used like a Social security number for non-citizens. Get her one and you can use it on the tax forms.

Individual Taxpayer Identification Number (ITIN) (http://www.irs.gov/Individuals/Individual-Taxpayer-Identification-Number-%28ITIN%29)

There is an error in your tax return filing. Your status on the year you get married up to present must be "married filing jointly". You must file form W-7, request for tax ID for your wife (ITIN). You cannot e-file.

What you should do now is file 1040X to amend the incorrect info on your tax return, together submit form W-7 to request for ITIN your wife.