The purpose of this study was to review the contents of the family ethics of Cho-Seon Dynasty in $oxdr$Sa So Jeol$oxul$written by Deok Moo Lee in 1775. The major findings on the family ethics of Cho-Seon Dynasty can be summarized as follows: 1) The marital relationship must keep to be equal, although they have different characters in the personality and different roles in the family. And husband/wife has to respect each other, to try to do for the marital harmony, and to treat nicely to his/her spouse. 2) In the parents-children relationships, children shoed respect and support their parents sincerely while parents’lifetime and perform an ancestral sacrifice wholeheartedly after parents’death. And parents haute the right and duty to educate their children. They have to teach their son to attend to his studies with diligence and teach their daughter to make efforts for the family and kin relationships. If parents or children are in fault, children shoed request to rethink the parents’fault to their parents earnestly and parents must also admonish their children with love. 3) In the sibling relationships, they have to show the fraternity each other. And the younger has to respect especially to elder brother.