This study aims to measure the effect of service quality and security on customer satisfaction and customer loyalty at Bank Aceh Syariah of Banda Aceh city (BAS Banda Aceh). Data were collected through questionnaires distributed to BAS Banda Aceh as many as 300 people. The sampling technique applied was nonprobability sampling. This study used PLS to test the research model. The results reveal the Servqual, security, satisfaction, and loyalty in BAS Banda Aceh are in good achievement, Servqual affects satisfaction, Security affects satisfaction, Servqual affects loyalty, Security affects loyalty, Satisfaction affects loyalty, Servqual affects loyalty mediated by satisfaction, and Security affects loyalty mediated by satisfaction. The satisfaction in the model also has been proven as a partial mediator. These findings also prove that the model for increasing customer loyalty at BAS Banda Aceh is a function of improving service quality, security, and customer satisfaction. Academically this tested model can be further developed with further research by adding other variables.