Digital games makes players stay game world as offering self-control narrative. In this points, quest, a purposive and performative narrative element, is suitable to explain the relation between flow and narrative. Unfortunately, a study on the relation between flow and narrative was not abundant. This study analyzed World of Warcraft which is a typical example of quest game to figure out the relation between quests and flow, and Csiksentmihalyi\'s theory is used for it. First of all, we discuss about the process of flow. Quest has a episodic format, so it helps a player can choice his own generating narrative. The content of quest is relate to hero\'s journey, and it makes player can not give up but keep to do a challenge. After a player experienced flow, he can have avatar\'s identity in mind. Because of a strong sense of virtual identity he can free from perception of actual time passage. Futhermore, flow can give a player a sense of subjectivity by providing feeling of management in the virtual world. This study try to suggest another point of view about flow in digital games. Flow provides some good functions for players. We should distinguish flow from addiction, and will find out the detail elements about flow in digital games. Key words: Flow, Csikszentmihaly, Quests, Process of Flow, Functions of Flow