This paper is aimed to make an inference to when the mask drama appeared in Korea. In order to reach this aim, I used a comparative study and took a three step discussion method. In the first step, I suggest a possible relationship between the Choson dynasty's 'sohakjihee(笑謔之戱)' and the contemporary mask drama. And I have found evidence to support this point. In the second step, I carried out a comparative study on relationship between the korean mask drama and tradition of 'songjaju(宋雜劇)'. And the results of this study confirmed my suggestion. The possible relationship was proved by several aspects. For example, both the korean mask drama and 'songjaju(宋雜劇)' consists of kwajang(科場) or duan(段), a dramatic form of mask drama and characters etc. In the third step, I tried to investigate the date of origin of the mask drama. Cnsidering several reasons, I concluded that the korean mask drama appeared during the Koryo dynasty at latest.