Marketing is a social and managerial process used by individuals, households, or organizations to obtain the needs and desires of individuals and organizations. The research aims to determine the relationship and influence of Relationship Marketing and Brand Image on customer loyalty at PT. Karsa Buana Lestari. This type of research seeks to find the relationship between relationship marketing and brand image and customer satisfaction and loyalty using consultant and laboratory services at PT. Karsa Buana Lestari. The research results show that there is a positive influence between relationship marketing and brand image on customer satisfaction. Relationship marketing and brand image also show an influence on customer satisfaction and loyalty. Customer satisfaction influences customer loyalty positively and significantly