The use of plants in traditional medicine has been seen, these compounds have not been studied in depth against hospital microorganisms. The present work aimed to determine the in vitro inhibitory effect of the liquid extract of Musa acuminata (banana var. Silk) at 5, 10, 20, 30% v / v on methicillin-resistant Staphylococcus aureus and evaluate the toxicity of Musa acuminata about Artemia salina. Five strains of methicillin-resistant Staphylococcus aureus infections from patients with respiratory tract infections and Musa acuminata liquid extract will be used. The number of experimental observations was 75 for the inhibitory effect and 120 for the toxicity. The inhibitory effect was determined following the sowing methodology by the method of surface extension and the bioassay of toxicity with Artemia saline nauplii. At volumes of 5.10, 20, 30% v / v of banana sap, 6.3x106 were obtained; 4.3x106; 2.3x106 and 0 CFU / mL respectively, the difference between them was statistically significant. Musa acuminata extract (banana var. Silk) on Artemia saline determined an average ratio between the exposure concentration and the LC50 of 22,553% v / v (2,255 mL), which is relatively harmless. It is concluded that the extract of Musa acuminata (banana var. Silk at complications of 5, 10, 20, 30% v / v had an inhibitory effect against methicillin-resistant Staphylococcus aureus species and is not toxic to Artemia salina.