This research aims to determine the influence of product quality and brand image on customer loyalty with service quality as an intervening variable. The type of research is quantitative research. The research population was customers of Bank Sulut Go, Ratahan Branch, Ratahan District, Southeast Minahasa Regency. Samples were taken from 100 customers using simple random sampling. The data collection technique uses a questionnaire. The data analysis technique uses Structural Equation Modeling- Partial Least Square (SEM-PLS). Based on the research results, it shows that product quality has a significant effect on customer loyalty as proven by the t test results which show probability values (p-values) are smaller than 0.05, namely 0.046. Brand image has a significant effect on customer loyalty as evidenced by the t test results which show probability values (p-values) are smaller than 0.05, namely 0.002. Service quality has a significant effect on customer loyalty as evidenced by the t test results which show probability values (p-values) are smaller than 0.05, namely 0.000. Service quality mediates the influence of product quality on customer loyalty as evidenced by the t test results which show a significance value smaller than 0.05, namely 0.000. Service quality mediates the influence of brand image on customer loyalty as evidenced by the t test results which show a significance value smaller than 0.05, namely 0.000.