Best case scenario--it won't be an issue. Worst case scenario--it not only disqualifies you from citizenship, but also lands you in removal proceedings and bars your from eligibility for a variety of forms of relief from removal.
Where you situation lies in that wide spectrum of possibilities will depend on things like:
--the exact statutory language of the criminal law under which you were convicted;
--the maximum possible sentence;
--the sentence you actually received;
--the date of the offense;
--the date you completed, or will complete, the terms of any probationary period;
--the nature of any other criminal issues in your past;
--whether the offense was ever disclosed from immigration officials;
--the identity of your victim;
--when you obtained your green card.
So, this is just a long-winded way of agreeing completely with the other attorneys here who were quicker to answer you--gather up all of your criminal records (for the offense and any others) and all of your immigration materials and schedule a consultation with a reputable immigration attorney in your area.
Do not file anything until you have a complete understanding of any potential vulnerabilities.