Saitama and Zeno are two characters from different anime series with vastly different power levels, abilities, and strengths. Saitama is the protagonist of the One Punch Man series, while Zeno is the Omni-King, the most powerful being in the Dragon Ball Super series.

Saitama is known for his incredible strength, speed, and ability to defeat any enemy with a single punch. He has trained his body to the point where he can defeat even the strongest opponents with ease, and his strength is said to be immeasurable. On the other hand, Zeno is an omnipotent being who can destroy entire universes with a single thought.
It is difficult to compare the two characters as they are from different universes and have different levels of power. However, if we were to consider their abilities and feats, it is highly unlikely that Saitama could defeat Zeno.
Zeno is a being who has the power to erase entire universes with ease. He can control time and space, create anything he desires, and has no known weaknesses or limits. Saitama, on the other hand, is a powerful hero with incredible strength and speed, but he has never displayed the ability to control time or space or create anything on the level of Zeno.
Furthermore, Saitama’s strength is physical, while Zeno’s power is more of a conceptual and existential nature. Even if Saitama were able to land a punch on Zeno, it is unclear if it would have any effect on the Omni-King, given his immense power.
In conclusion, while Saitama is an incredibly powerful hero, it is highly unlikely that he could defeat Zeno, given the Omni-King’s abilities and power.