There are limited studies on the relationship between internal marketing and service quality in Uganda though in the west interest in internal marketing seems to have intensified from 2006 onwards,[1]. Customers no longer simply pay for services: they co –produce with the contact employees at the time of transaction and therefore the customer buying experience has to be understood from both the employees’ and customer perspectives, [2] The purpose of this study was to establish the relationship between internal marketing, employee job satisfaction and service quality. Survey research method was used with the primary data being collected from 91 employees and 96 clients of one selected firm in the aviation industry in Uganda. The study results showed that Internal marketing has a strong positive correlation with service quality (r=0.723**, p-value< 0.01) while internal marketing and employee job satisfaction are significantly correlated (r=0.871**, p-value< 0.01) and are strongly positively correlated. Employee job satisfaction showed a significant positive correlation with service quality (r=0.895**, p-value<0.01). The practical implication of our study is that internal marketing has a fundamental contribution in the delivery of service quality. The study findings inform managers, who have hitherto tended to put more emphasis on the external customer, to change their perspective as taking the internal customer for granted may result in negative outcomes for their organizations.