Teacher social competence is one of the competency standards that must be improved nowadays in consideration to the rapid development of technology which erodes the social abilities of the community, including teachers. The principal as a school manager has a very important role in improving the teachers’ sosial competence. This study aims to know the principal’s strategy in improving teachers’ social competence at MTsN 6 Tanah Datar. The type of this research is a case study with a qualitative approach. The research location is at MTsN 6 Tanah Datar. The research informants were the principal and the teachers at MTsN 6 Tanah Datar. Data collection techniques used are through interviews, observation and documentation. Data analysis technique is by data condensation, data display, drawing conclusions and data verification. The result showed that the implementation of teachers’ social competence at MTsN 6 Tanah Datar was good by being able to reflect objective and non-discriminatory actions, interacting with courtesy, polite and empathy, adapting to the workplace environment and students, and being active in community activities and fellow teachers both orally and written. The principal’s strategy in improving teachers’ social competence at MTsN 6 Tanah Datar is interesting and has never been done before by principals in other schools, namely: holding a recitation program by inviting religious leaders, conducting teacher social attitude development by inviting sociologists, developing teacher mental attitudes and personality by inviting psychologists and involving teachers in regional meetings, traditional events or other meetings invited by outsiders.