Gender: Male
Age: 19 (beginning); 21 (current)
Birthday: March 3
Height: 193 cm
Weight: 85 kg
Hair color: Brown (1999), Black (2011)
Eye color: Green (1999), Brown (2011)
Blood type: O
Occupation: Hunter, Medical Student
Nen type: Emission

Prior the hunter exam, Leorio's close friend died to a curable illness. Despite being curable, Leorio was unable to save his close friend due to his lack of money and knowledge. He aims to become a doctor - one that will help those even without the money to pay for treatment. He decides to take the Hunter Exam in an attempt to earn money for tuition fees and medical treatment for others.

Leorio is talented at bargaining, being able to haggle shopkeepers to no end. He may at times seem brash and rude, but in the end is very kind towards his friends.