With our present understanding of the universe, the answer is very probably. Any god that exists has only ever acted within the laws of physics.
More precisely, regardless of your definition of a god, there is no extant evidence that the laws of physics have ever been violated.
Now, there are a number of reasons why we may find that this isn't true:
- we have an incomplete understanding of the laws of physics (almost definitely true)
- we aren't aware of every event ever (definitely true)
- there have been violations that we haven't witnessed (not unreasonable)
- the gods exist but haven't bothered to do anything (both scientifically and theologically tricky)
What we can reasonably safely say though, is that any regular action that a god takes in our bit of spacetime e.g. answering prayers, either doesn't violate the laws of physics or the gods are being super sneaky about the violations.
Edit. As Arthur has correctly pointed out in the comments, this answer assumes the existence of a god or gods. This assumption was present in the question so I felt it reasonable to answer with that assumption intact.
For the record, I do not rule out the possibility that there are no god or gods. Though any clear determination in that regard would render Philosophy.SE much less fun.