Superman has enough power to shatter whole solar systems in one shot. Of course Galactus is a giant being of power and crushes whole planets. In the end he lacks the speed of Superman. Superman is so much faster than the speed of light that it’s not even funny. Superman takes this match in an instant. Superman wins.
DReager1.com 
Earth-One Superman perhaps, but it’s a long shot. Post-Crisis Superman gets wrecked without even knowing what happened.
I think Post Crisis may still have a shot thanks to his speed advantage. Galactus is so big, that he might not be able to land a clear shot on Superman
This is what happens when you don’t read comic. For one superman cant shatter entire solar system with any punch. He’s not held back several times before an barely destroyed the moon even he admits he can’t destroy a planet in one shot on multiple occasions.
Second galactus isn’t limited to planets he literally eaten planets stars an the universe an could eat more but he says he’d be lonely. Now to address the rest of this fanboy stupidity.
No where has it ever been shown superman is to fast for a force of nature lije galactus. Galactus tags people with much faster travel speed (since people like this don’t read comics they just base this off him flying in a striaght line on Google scan) so thir can criss the universe in a few seconds an it takes amped superman to month going by that logic thor should ko him everytime. Same with gladiator and silver surfer but they don’t an all if them can unlike superman one shot a, planet or galaxy but they don’t beat galactus an even get tagged by him quite easily.
Now superman speed he’s tried to blitz plenty of people but to date has only won o ce against zod who he had to catch by suprise every other so called speed he used in a fight against much weaker beings leads to him giving up because it doesn’t do any damage an going back to striaght brute force.
Superman looses this fight the sane way he did via the crossover one eye blast an koed for 3 pages. Only a complete idiot or superman fanboy who doesn’t read comics would be dumb enough to think superman who never wins a fight via speed is going to be to fast for galactus who tags faster beings every other day
Nah man, you’re underestimating Superman here. Keep in mind that with a sneeze he nearly destroyed a solar system so a punch would definitely do the trick. Silver Age counts since it’s composite. Galactus has trouble tagging the Fantastic Four before they hit him with the Nullifier. He’s not doing anything against a speedster like Superman