From the study of the social structure of the Lao Song, the findings are that rituals are the significant factors maintaining the community’s unity and the rituals indicate the status of individual and the group. The status is different depending on sex, not age, education and occupation. Men have higher status than women. A family organization is determined by the kinship system symbolized by the belief in the same “phi” and that the kinship is unilateral and patrilineal. The Song’s concept of the community is not based on territory, but kinship of both consanguinity and affinity, for example, in-law, daughters-in-law, and nieces-in-law who are regarded as “being of the same phi”. Besides, social stratification based on the clan or family is also mirrored in the Song community. There are two classes of clans or families-“phu-tao” and “phu noi”. However, the Song is an open community in the sense that young Song from these two classes can marry each other, resulting in the changes of the female status from high to low or vice versa according to their husbands’ corresponding status.