The aim of our study was to evaluate the antibacterial properties of various extracts from the bark of Pericopsis laxiflora on Escherichia coli and Klebsiella pneumoniae, two strains of beta-lactamase producing extended spectrum (ESBL). The method of wells in the agar was used to test the sensitivity of bacterial strains while the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined by the dilution method in liquid medium. The methanolic, acetatic and ethanolic extracts 70% gave inhibition zone diameters between 8 and 12 mm on the strains tested. Moreover, these extracts showed bactericidal powers of E. coli ESBL and K. pneumoniae ESBL with MIC and MBC ranging from 12.5 to 50 mg / mL. However, only the acetatic fraction gave the lowest CMB both E. coli ESBL (12.5 mg / mL) on K. pneumoniae ESBL (25mg/mL). The sensitivity of the bacteria tested justifies the use of this plant in traditional medicine to combat diseases in which the tested germs are involved including urinary tract infections and gastroenteritis.