The purpose of this thesis is to study the growth story of Gang Gam-Chan who was a hero in the Goryeo Dynasty. The growth story of Gang Gam-Chan has been connected with `the star falling birth story`, `the eccentric things birth story` and so on, and has played the role that reveals a God-given ability shown by mythical characters. There are not many documents about the growth period of Gang Gam-Chan, but the summary is as follows. Gang Gam-Chan was recognized as the child brought from without. He was small and ungainly, but had the marvelous and strange ability potentially. Although he entered government service in his later years, he was the man who liked reading from childhood and had many stratagems. Traditional tales handed down orally about the growth period of Gang Gam-Chan have shown many different sides of him unlike documents. The growth period of Gang Gam-Chan showed in the traditional tales handed down orally was revealed into several parts such as `the learning process`, `the appearance`, `the suffering from the smallpox` and `the eradicating the changed eccentric groom`. The learning process of the growth period of Gang Gam-Chan is mostly natural. His natural ability is related to `the star falling birth story` and `the eccentric things birth story`. He didn`t need any special learning process because he had a natural-born ability. As to the appearance of Gang Gam-Chan, there are two kinds. One is natural, and the other is acquired. In the case of the former, it was described that he was out of a fox. In the case of the latter, it was described that he suffered from the smallpox and became ugly. In `the suffering from the smallpox`, it was explained that Gang Gam-Chan was born with good looks, but made his appearance ugly for a great work. This emphasized his will of the growth period, and showed his heroic aspects. `The eradicating the changed eccentric groom` is the prologue to reveal the outstanding ability of Gang Gam-Chan. Through this, it is showed that Gang Gam-Chan`s ability has been already completed while growing up. Later, this is connected with his absolute ability showed in his stories. As a result, Gang Gam-Chan developed into the mythical hero who could defeat ghosts as well as animals such as tigers, foxes and so on.