Sung Jin-Woo is the fictional protagonist of Solo Leveling, the web novel and webtoon by Chugong that was adapted into the A-1 Pictures anime. He starts as the weakest E-Rank hunter in South Korea, then is selected as the Player of a mysterious System and grows without limit until he becomes the strongest hunter on Earth. His father vanished in a dungeon and his mother fell into a coma, so he became the family's breadwinner while still young.

He is known for a calm, understated manner and for letting his actions speak. Once timid, he speaks with growing confidence as he levels up, and his dry humor shows most with his sister Jinah and his wife Cha Hae-In.