Infection diseases are still a major health problem in developing countries. gotu kola (centella asiatica (l.) urban.) is one of the herbs that many people use to treat various diseases. this research’s is aim to determine the antibacterial activity ethanol extract of gotu kola (centella asiatica linn.) in inhibition the growth of pseudomonas aeruginosa. the method of this research is laboratory experiment using completely randomized design which was divided into 6 treatment groups and repeated 5 times. the treatment group consist of ethanol extract of gotu kola with 12,5%, 25%, 50% and 75% concentration. positive control that was used is meropenem 10?g and negative control that was used is aquades. antibacterial activity test was used kirby bauer disc diffusion method. data of this research were analyzed by anova and followed by honestly significant difference test. the results showed that ethanol extract of gotu kola with concentration 12,5%, 25%, 50% and 75% provide average