Hypertensive disturbances during pregnancy are the leading cause of maternal and fetal death; unfortunately, no effective treatment exists. Therefore, interventions that reduce the likelihood of developing preeclampsia during pregnancy are required. This study aimed to see how Progressive Muscle Relaxation (PMR) compared to breathing exercise techniques affected Blood Pressure (BP) levels among mildly preeclamptic pregnant women. A convenience sample was used in a quasi-experimental study of 75 mild preeclamptic pregnant women in the Obstetrical Outpatient Clinics at the Suez Canal University Hospital in Ismailia, Egypt. They were divided into three groups: study group [I]: the deep breathing exercise group; study group [II]: the PMR group; and study group [III]: the control group. Data were collected using two methods: an interviewing information collection tool and a physiological measurement tool. There was a statistical significant difference in systolic and diastolic blood pressure after six weeks of training among intervention groups (PMR and breathing excercise technique with p value 0.001 for both groups) compered to contol group. However, there was no statistical difference in BP (systolic or diastolic) after two weeks of intervention among the three groups. PMR and breathing techniques could effectively control BP in pregnancy complicated by mild preeclampsia. Both techniques could be introduced in routine antenatal care for women diagnosed with mild preeclampsia. Health and fitness professionals should focus more on preparing and delivering various sports programs incorporating various muscle relaxations and breathing techniques.