The study aim was to evaluate the impact of using body mechanic principles on improving low back pain among female workers at Benha University. Aquasi experimental design was used in the study. A sample of convince 150 of female workers was selected. The sample was divided into study and control groups. The study was conducted at the Rheumatology Outpatient Clinic in Benha University Hospital and Health Insurance Hospital. Three tools were used for data collection. 1) An interviewing questionnaire to assess the studied participants characteristics and personal habits. 2) A functional capacity assessment rating scale (Aberde low back pain scale , 2004) this sheet covers assessment of pain characteristics and variety of activities as daily activities, personal characteristics, social life, rest and sleep. 3) An observational checklist to measure weight and height of studied participants, body posture during sitting, studying, lifting, walking, work and home duties. Result revealed that The study group of female workers who had fewer intermittent pain was less than those in the control group (52.5% vs 60.0 %), frequent daily pain was less between the study group than the control group (63% vs 25%) also, in the immediate posttest study group who had no activity restriction were more than female workers in the control group (8.7% vs 0.0 %) in the follow-up test. Female workers in the study group who had no activity restriction were more than female workers in the control group (26.3% vs 0.0 %). This study concluded that using of body mechanic principles improved the back pain dependency level among female workers in this study group; therefore, it was recommended that body mechanic principles must be used by female workers having low back pain.