This study aims to identify the forms of interpersonal communication in improving the performance of principals, both individually and collectively conducted in several high schools in the city of Manado. The research method is descriptive research to identify the definition of research in justification with the correlational research method. The population in this study was the High School Principal in the city of Manado. Samples were taken 50 randomly. The results of the study are that there is a positive relationship between Interpersonal Communication and the Performance of the Principal of Senoir High School, Based on conclusions and seeing facts in the field, to improve the Performance of High School Principals, Interpersonal Communication must be improved.