Soap is a pharmaceutical product that humans need every day to clean dirt and oil from the body. Soap is a sodium and potassium salt of fatty acids derived from vegetable oil or animal fat. The utilization of saga leaves in the formulation of solid soap preparations can be used as an alternative treatment for bacterial infections. Saga leaves (Abrus precatorius L) have antibacterial active ingredients such as flavonoids, saponins, and tannins. The purpose of this study was to determine the antibacterial activity of saga leaves when applied in solid soap in inhibiting Staphylococcus epidermidis bacteria. This study uses the disk diffusion method with 3 variations in the concentration of saga leaf ethanol extract, namely F1 (3.6 grams), F2 (6 grams), F3 (8.4 grams). The results showed that the preparation of solid soap with the addition of ethanol extract of saga leaves affected the physical quality of solid soap, namely dark moss green soap with a bitter aroma typical of saga leaves and a slight aroma of greentea, the results of the foam height test obtained results as high as 70.3-90.3. The pH test results on saga leaf solid soap are 10.07-10.97 and the water content test results are 7-9%. The antibacterial test results of solid soap preparations that showed the highest inhibition were F3 (8.4 grams) with an inhibition zone diameter of 10.58 mm. The data from the foam height test, pH test, water content test, and antibacterial test were statistically processed, and obtained the results of significantly different test data, namely <0.05, which means that the difference in the administration of ethanol extract of saga leaves (Abrus precatorius L) has a different effect on each preparation quality test result and antibacterial test result. The size of the inhibition zone formed indicates that the solid soap of ethanol extract of saga leaves (Abrus precatorius L) can be used as an alternative treatment for bacterial infections of Staphylococcus epidermidis.