Goku would win
Superman has to accelerate to pass light speed, and Goku can teleport. Superman can maybe destroy planets with some effort, but Goku and Beerus are literally strong enough to destroy the entire universe with one energy attack. Beerus taps a planet with one finger, and it explodes. Just the shockwaves from their punches destroy planets and stars light years away. Akira has already stated Goku will soon be more powerful than Beerus or Whis. SSG Goku can heal his injuries and because he's a Saiyan it makes him even stronger. Superman is outclassed in every way at this point. Goku VS Superman is not a fight anymore.
Goku is not only a god, but a god that keeps training to become stronger than other gods. Superman is a god (Superman Prime), but he doesn't train.
Because Superman is Amazing
Too damn easy. New 52 Superman - wins. Post crisis Superman - wins. Kingdom Come Superman - wins. Pre crisis Superman - wins by a stomp. Superboy Prime - wins by a stomp. Superman Prime - wins by a god-stomp. Cosmic Armor Superman - wins by not even a damn question. DCAU cartoon Superman - loses. That's right. The only version of Superman that Goku can defeat is the cartoon one.
Not even close!