First, you probably need to define "god". Does a biological being like us but with extremely advanced technology count? Or do they need to be able to exist beyond conventional physics and have apparently limitless power in our universe, like Q? Or do you mean specific gods, namely the ones which various groups of humans worship?
If it's #1, those are just aliens. If #2, I don't think you can discount the possibility entirely, but there's no evidence for their existence, but it's entirely possible. But spending any energy on the question seems a bit pointless, since no members of the Q Continuum have made their presence known to us yet. If #3, the problem there is there's no good evidence for their existence, only ancient stories passed down from oral tradition, and the old "telephone game" shows how reliable that is, plus the well-known phenomenon of hallucination, which can happen to people when they eat certain tainted foods.
The question of aliens is worth considering seriously because we do know that life is possible (look in the mirror), we know under what conditions if can form (look outside; we have a planet to study that formed life), and now we know that lots of other planets are out there, and some of them may very well be similar to our own. If we can evolve here, it's quite possible some other beings evolved elsewhere under similar conditions. And with many billions of stars out there (just in our galaxy and nearby ones), the probability of other planets existing with conditions similar to ours is high. Furthermore, as our ability to detect exoplanets improves, it's quite possible we may detect signs of alien life: radio signals, industrial emissions in their atmosphere, weird starlight patterns indicating a possible Dyson swarm, etc. There's no way to detect any kind of god (whether it's one from some old book or the Q).
We have proof that life exists here, so we know it's physically possible. It appears that physics works more or less the same everywhere, and the universe is really big.
