Gon is a young boy with long spiky black green tipped hair and large, hazel brown eyes. His usual outfit is composed of a green jacket with reddish edges covering a black or white tank top underneath, green short shorts, and green, laced boots. In some arcs such as the Greed Island and Chimera Ant arcs he takes off the jacket and wears only the tank top. In the Greed Island arc and at the beginning of the Chimera Ant arc he wears the Paladin's Necklace, a Greed Island card with the ability to purge any external effects to a card the wearer is holding.
Gon is an athletic, rustic, and friendly boy who is searching for adventure. Also, he isn't very good at math. However, having spent a lot of time in the woods as a child, he is very good with animals. Gon is an Enhancer, who are known for being simple-minded and determined. This determination and talent leads to both potential allies and potential enemies trusting in him and taking his side. He has inhuman senses; Gon has a heightened sense of smell almost like a dog and has very good vision, as well as having very keen taste. Gon wants to become a Hunter because he wishes to find out the depths of an occupation that would cause a father to choose the profession over being with his own son.
Simultaneously, his flaws lie in his temper and impulsive nature. Gon sometimes fails to think things through and such actions lead to him suffering. Though possessing talent far beyond the norm for his age, anytime his abilities are challenged, he feels as if he has to prove his antagonist wrong. He continually strives to obtain greater power, often becoming exceptionally stronger in his anger. But Gon's anger also leads to extremely reckless tendencies. When his emotions are ignited, Gon becomes irrational and completely oblivious to anything else. While his will is stronger than most and he can be very level-headed, but this clear mind can also make him very cold at times. Even more worrying is the extent to which his simple mindedness colors his perception of those around him. Often it's difficult for others to understand or relate Gon's actions or thoughts to what people would consider "normal" thinking. On more than one occasion the people around Gon have remarked on how he "doesn't care about the good or the bad" with some believing Gon to be a little insane.
Gon is extremely confident in his abilities. Sometimes, he does not realize when the opponent is far stronger or even after he knows the opponent is stronger than him; regardless, he will continue to fight. He refuses to accept himself as inferior to any opponent that he disagrees with, including those clearly stronger than him. Togashi initially portrays this as naïveté. Aside from becoming a Hunter and finding his father, Gon desires strength above all else. Gon's greatest insecurity lies in his own weakness and not being able to protect those close to him.
At the age of twenty, Ging Freecss returned home to Whale Island for the first time in eight years carrying his infant son, Gon. When questioned about the child's mother, Ging simply mentions that the pair had separated. While Ging tries to leave Gon in his grandmother's care for a little while, Ging's cousin Mito is infuriated at Ging's parenting and gets custody through the courts (this is odd because she would only have been 13 at the time). Ging leaves Whale Island, never to return.
Since his early youth, due to his father's absence and Mito's dislike of Ging, Gon had been told that his parents died in an accident when he was a baby. But at the age of nine, Gon is rescued from an angry mother foxbear by a man named Kite a professional Hunter and a student of Gon's long lost father. After hitting Gon in the face, Kite attempts to kill the foxbear's cub but Gon protects it. Kite is looking for Ging as a final test before his master will consider him to be a true Hunter. Kite's admiration of Ging awakens in Gon a lifetime goal of meeting his father. In order to find and meet Ging, Gon is driven from that moment to obtain a Hunter's License. He sights a desire to know what would cause Ging to choose his profession as a Hunter over being a parent as his motivation for becoming a Hunter.