My question is I have criminal record (in my country). Can it affect my green card application? I am worrying about this for some time now.

Yes, a criminal record can affect your green card application. It depends on the type of crime. Consult an immigration attorney to assess your situation.

Depends on the gravity of the crime. I think you should seek some legal advice from an immigration lawyer.

Depending on how serious the crime is, I think it can definitely affect