Despite its close connection to many of the problems related to uncloaking hidden structures of settlement aggregation in China, researchers have shown limited interest in quantifying and analyzing the social force. In this study, a sociogram approach for studying the social force in settlement aggregation was proposed and tested. Genealogies in different historic periods were used as the raw data for tracking blood relationships. The strengths of the approaches are the extraction and visualization of historical sources. Social force represents the effect of the environment on the behavior of person, and it evokes the people's motivation to act as a reaction to information he/she obtained from the environment. It is believed that the processes of settlement aggregation are the results of the social field acting on the behavior of the person. The sociogram model calculated by computer showed that it has the capability of describing the self-organization processes of settlement aggregation.