A friend of mine was in a brief relationship with a girl and as a result a child was born.
At this point neither of them know for sure who the father is since she was with several people at the time.
The girls is asking my buddy to take a dna paternity test.
Is he obligated by law to do it?

When the court orders it, he will have to.
I would assume you would want to know.

This is a legal question not a health question and has been moved. You should wait until a court orders such a test. But when it does you have to submit.

As said, just at her request no. However, the court will order the DNA test for whomever could be the father so at that point the answer becomes yes.

Why would you ask if YOU had to take the test if the thread is about your "buddy"?

I will also mention that only Court-recognized testing facilities are acceptable; home DNA kit results are not accepted.

(And - good catch!)