Infectious diseases are still one of the important public health problems to be considered, especially in developing countries. Mangosteen Leaves (Garcinia mangostana L.) is one of the well-known plants that are useful as antioxidants, antibacterial, and anticancer. This study aims to determine the chemical content and antibacterial activity of ethanol extract, n-hexane fraction, ethyl acetate and water of mangosteen leaves (Garcinia mangostana L.) on diffuse Staphylococcus aureus and Pseudomonas aeruginosa. Mangosteen leaves were extracted by maceration using 96% ethanol then continued by fractionation using a liquid-liquid extraction method. Mangosteen leaf extract and the fraction obtained were then tested for antibacterial activity with a concentration of 12.5%, 25% and 50% using disc diffusion method. The positive control used was ciprofloxacin 5μg / disk and negative control using 5% Tween 80. Identification of compound groups can be done using Thin Layer Chromatography (TLC) method. The results of antibacterial activity testing showed the zone diameter inhibition of gram-positive bacteria generally tends to be greater than gram-negative bacteria. The diameter of the largest inhibitory zone in Staphylococcus aureus bacteria is found in the water fraction of mangosteen leaves at 50% concentration with inhibitory zone diameter (10 mm), in Pseudomonas aeruginosa bacteria found in the water fraction and extract with a concentration of 50% has a inhibitory power of (8 mm). The TLC test results showed that in the extracts and fractions of mangosteen leaves contained flavonoids, saponins and steroids.