The study aims at identifying, through structure model, the relationship characteristics between a private security company and its service customer as well as the relationship between the service quality and the consumer behavior, thereby providing the practical services that may attract new customers and maintain the existing customers in the competition to survive in the same industry and also may raise the loyal customer base, providing academic fundamental data to set up aggressive relationship marketing strategies. To achieve such purposes above, the research was conducted with 229 subjects, the users of a private security company's service as the employees of the stores located in Cheonan area, using the convenience sampling. The data was treated, using the statistics program, SPSS Windows 18.0 Version for frequency analysis and reliability analysis. Additionally, the confirmative factor analysis and covariance structural analysis were made, using AMOS 18.0 Version. Through the data analysis following the research methods above, the conclusion was acquired as follows: First, the relationship characteristics of a private security company makes influence on service quality. Second, the service quality of a private security company makes influence on consumer behavior. Third, the relationship characteristics of a private security company makes influence on consumer behavior. Fourth, the service quality makes an influence as the mediate effect between the private security company's relationship characteristics and consumer behavior.