Sung Jinwoo — The protagonist and a Hunter. Originally the weakest E-Rank Hunter, he grows into the strongest Hunter and the Shadow Monarch by leveling up through the power of the 'System.'

Cha Hae-in — An S-Rank Hunter and the Vice Guild Master of the Hunters Guild. A swordsman-type Hunter with fast swordsmanship and excellent combat instincts, she shows a special interest in Sung Jinwoo.

Choi Jong-in — A Korean S-Rank Hunter and Chairman of the Hunters Association. A fire-attribute mage-type Hunter who uses powerful wide-area flame magic, he plays a leadership role overseeing Korean Hunters. He is a character who plays an important role in gate response and Hunter management with his cool-headed and strategic judgment.

Baek Yoonho — An S-Rank Hunter and the Guild Master of the White Tiger Guild. A Hunter with beast-transformation abilities and powerful melee combat skills, he is a character who quickly recognizes the strength of an opponent with his sharp senses.

Ma Dongwook — The Guild Master of the Fame Guild and an S-Rank Tanker Hunter. A reliable shield-type Hunter who fights on the front lines with overwhelming defensive power and monstrous physical strength.

Lim Taegyu — An S-Rank Archer and one of South Korea's strongest Hunters. Possessing a calm and cool personality, he suppresses enemies in an instant even from a long distance with his overwhelming archery skills.

Igris — A powerful knight-type Shadow Soldier clad in red armor. A core force who protects Sung Jinwoo with quiet but overwhelming swordsmanship and loyalty.

Beru — The strongest Shadow Soldier, formerly the Ant King. He possesses incredible speed and overwhelming power, and is absolutely loyal to Sung Jinwoo.

Iron — A loyal Shadow Soldier who follows Sung Jinwoo even in death. He is characterized by excellent strength and defense, and a heavy combat style.

Go Gunhee is the Chairman of the Korean Hunters Association in Solo Leveling and a top-tier S-Rank Hunter. Despite his old age and chronic illness, he possesses a strong sense of responsibility and justice, and was the first to recognize Sung Jinwoo's potential. He is a respected hero who fought for humanity until the very end.