Preeclampsia is a progressive disorder affecting multiple systems, which is distinguished by the sudden appearance of high blood pressure and protein in the urine or other significant end-organ dysfunction. Progressive muscle relaxation techniques is a useful technique to minimize stress, anxiety and blood pressure among pregnant women with preeclampsia. The aim of this research was to evaluate the effect of progressive muscle relaxation techniques on physiological parameters, psychological factors and sleep quality among pregnant women with preeclampsia. Design: A quasi experimental design (Two-Groups, Pre-test / Post-test). Setting: The research was conducted at obstetrics & gynecological outpatient clinic in Benha university hospital. Sample: A purposive sample of 60 pregnant women with mild preeclampsia. Data collection tools: Five tools were used: A structured interviewing questionnaire, Self-rating anxiety scale, Cohen perceived stress scale and Pittsburgh sleep quality index. Results: The total score of knowledge and sleep quality in the study group showed significant improvement post-intervention and two weeks post- intervention compared to pre intervention while in the control group, there was minimal improvement. Also, the physiological parameters, total level of anxiety and total level of stress were significantly decreased in the study group post-intervention and two weeks post- intervention compared to control group.  Conclusion: The progressive muscle relaxation technique was effective and have a significant improvement of knowledge, physiological parameters and psychological factors and sleep quality among women with mild pregnancy induced hypertension. Recommendation: Pregnant women with hypertension should be provided with relaxation techniques in antenatal care to improve knowledge, physiological parameters and reduce blood pressure and stress level.