Hi all,
Great place for people with questions. Thank you for this.

I am a US citizen and have recently applied for permanent residency (green card) for my parents. So the application is in the works.
Now my dad needs to come to the US for an operation in a couple of months. He has been here many times on visitor's visa. Will he automatically be denied a US visa because of the green card application?
I really appreciate your answer.

Dude

Yes. Once sponsorship application in filed, visit visa is not allowed. For medical treatment, your father will have to declare about surgery and that takes long time and there are lot of conditions for medical Visas.
Good luck.

Yes. He will not be allow to visit if the petition is pending.

That was quick. Thanks guys. I really do appreciate it. I will have to make other arrangements. He is a surgeon himself and has friends around the world. I guess we will have him go to London.
Thanks again. This is a wonderful site. Please keep it up guys.