Purpose: The purpose of this study was to identify the effects of an extreme heat Adaptation Program on the blood pressure, stress response, self-efficacy, and knowledge of management of hypertension and extreme heat of patients who suffered from hypertension. Methods: A quasi-experimental study with a non-equivalent control group pretest-posttest design was used. The data collection period was between July 2 and August 20, 2012. Thirty-seven patients participated in the study (18 in the experimental group and 19 in the control group). Data were analyzed using χ²-test, t-test, and Cronbach’s alpha coefficients with SPSS/WIN 19.0. Results: Patients who participated in the program showed statistically significant improvements in systolic blood pressure (SBP), self-efficacy, and knowledge of management of hypertension and extreme heat. Conclusion: The results indicate that this extreme heat adaptation program can be utilized for patients suffering from hypertension in order to reduce their SBP and to increase self-efficacy and knowledge of management of hypertension and extreme heat. Therefore, it is recommended that this program be used for elderly patients suffering from chronic disease.