This research aimed to study significant relationships among factors influencing customer satisfaction and loyalty in the health care service industry. In order to test the conceptual framework, structural equation modeling (SEM) was used to analyze the data from 252 respondents (outpatients) at four public and private hospitals in Khon Kaen City, Thailand. This empirical research determined how the health care service image, service quality, and behavioral intentions were interrelated using a scale adapted from Taiwan Customer Satisfaction and American Customer Satisfaction Indices, as the perceived quality variable was designated as a second-order construct. The findings showed that the significant factor impacting customer loyalty is customer satisfaction. Corporate image significantly enhanced both customer expectations (CEs) and perceived service quality. The researchers also observed that perceived service quality was positively related to tangibility, instrumental, and emotional supports in addition to customer satisfaction. In conclusion, this article proposed a thoughtful research scenario for management and corporate/public policymakers at the national level in Thailand. It was observed that a good image could directly enhance perceived service quality for businesses in the health service sector. Short Abstract We aimed to explore the relationship between image, service quality, and patient loyalty in the health service sector. A multivariate analysis (structural equation modeling) was employed to analyze the data from 252 outpatients in Khon Kaen City, Thailand. The conventional service quality model suggests that corporate image influences customer expectation, and then affects perceived service quality, then customer satisfaction, and finally, loyalty. However, this article found that, in the health service sector, a corporate image may directly influence perceived service quality without the customer expectation variable as a mediator.