The purpose of this study was to determine the effectiveness of motivational interviewing (MI) on physical and Mental Health Indicators in patients with essential hypertention. Subjects were first screened using the inclusion and exclusion criteria. Therefore, 26 hypertensive patients, by using convenient sampling method were selected and randomly divided into experimental and control group (13 patients in each group). The MI group were treated in 5 sessions and while the control group did not receive any treatment. This study was a semi-experimental study with a pretest, post-test and follow-up. Results showed that there were significant differences between two groups in psychological well-being and its subscales, cognitive fusion and systolic and diastolic blood pressure. So, motivational interviewing is an effective intervention in essential hypertensive patients.