The main objective of this research is to investigate patients' mindsets concerning the emerging green hospitals and the patients' willingness to receive services and pay for them at these hospitals. Using a descriptive correlation survey research design, the study sampled 402 respondents from public (N=201) and private (N=201) hospitals of Thailand. The results suggest that the respondents agree regarding their attitudes, expectations, and perceptions of practices and principles. Moreover, respondents are willing to pay more for green hospital services. Finally, in considering whether there were significant predictors of willingness to pay more for green hospitals, the study found a number of significant variables including gender and various beliefs and attitudinal variables. These results suggest that the theory of planned behavior, describing attitudes, subjective norms, and perceived behavioral controls offers a rational choice model for understanding consumer behavior. Recommendations for additional research and green hospital management are provided.