Korean marriage is adopting a declaration of marriage or civil marriage requiring a certain form prescribed by law. Therfore, even if a husband and wife live together as a couple, if they do not report their marriage properly, they can not be legally recognized as a couple and can not receive various legal rights and protections that are recognized among married couples such as inheritance. This is the story of the movie and TV actor and actress Park Yoo-hwan's common-law marriage, who took a big part in the media on August 3, 2016. As Korea is expected to enter the super aged society of more than 32.4% by 2040, the issue of the protection of the common-law spouses is emerging as a new law issue. In the case of elderly people, even if they remarry, many sons and daughters of them disagree with their parents' marriage report because of property inheritance problems. Many remarried elderly people are living with common-law marriage. In the case of elderly people, even if they remarry, many of their sons and daughters disagree with their parents' marriage report because of property inheritance problems. Many remarried elderly people are living with common-law marriage. However, in this case, if their partner dies, they may be in a situation where they have to worry about livelihood. Especially, if they are living, and common-law marriage relationship is canceled, arrangement of marital property and etc. by property division are possible. Therefore, they can be protected. However, if common-law marriage relationship is canceled by death of one of the spouses, the right of inheritance is not recognized also, the claim for division of property is not recognized. Therefore, there are many unfair points in terms of equity, as well as the support of surviving spouses. Thus, It is true that the position of the courts in Korea is also sympathetic to the necessity of legislative alternatives. Therefore, in order to examine these problems, this study examines the general theory of the common-law marriage and after analyzing the trends of countries about the common-law marriage, this study will try to find the new ways of dealing with the common-law marriage in Korea.