Subrogation action by an obligee is a lawsuit where a person, holding the subrogation right of the obligee under civil law, files a lawsuit by right of subrogation. According to civil law, subrogation action by an obligee recognizes the obligee to hold the right of performing the litigation of existence and nonexistence on behalf of the original right holder, the obligor; thus it is acknowledged that the obligee is holds a statutory standing in such case. As far as the legal nature of subrogation action by an obligee is understood as the litigant with statutory standing, it is appropriate to consider that the existence of claim to preservation is related to the existence of standing and is applicable to the requirements for litigation. Therefore, in case an obligee without claim to preservation files a subrogation action, the action is considered unlawful as it does not hold a standing. When a subrogation action (competition of subrogation action) filed independently by multiple obligees or pendency of a lawsuit filed by an obligee or an obligor,in case an obligor or an obligee files a lawsuit later, the later and previous lawsuits become duplicate lawsuits because the litigants or subject matters of each action are the same. During the pendency of a subrogation action by an obligee filed without claim to preservation, a defect occurs between standing (previous lawsuit) and duplicate (later lawsuit) lawsuits and the two compete as another obligee with claim to preservation each files a lawsuit later against the same obligor.As a solution to resolve the competition of defect between standing and duplicate lawsuits due to a lack of claim to preservation, in principle, the principle of investigation order for litigation requirements must be applied. However, in cases where the practical resolving of the conflict or the protection of practical obligee is violated, the application of such principle must be limited; in such case, this study suggests a solution that can resolve the conflict and protect the obligee.