Service oriented organizations are increasingly becoming the order of the day globally, hence there is increasing demand for the services of Telecommunication companies as well as increasing concern for the quality of the services provided especially as they affect customer satisfaction. This study investigated the effect of service quality on customer satisfaction in 9mobile Nigeria. Survey research design was employed in the study. Primary data was collected through self-administered questionnaire issued to the respondents using purposive sampling technique. The data was collected from a sample of 499 subscribers of 9mobile Nigeria. Partial Least squares - Structural Equation Model (PLS - SEM) was used to analyze the data collected. PLS - SEM was also used to test the hypotheses formulated for the study. The findings revealed that reliability and tangibility have positive and significant effect on customer satisfaction while assurance, empathy and responsiveness have positive but insignificant effect on customer satisfaction. The study recommended the need for 9mobile Nigeria to invest more in technology and training of staff to enhance high quality services and increase customer satisfaction.