The objective of this study has been to identify and to classity the antibiophenotypes of resistance to the betalactams in the Pseudomonas aeruginosa strains agaist three antiPseudomonas betalactams and the association of one of these with an inhibitor of betalactamasc. Seventy non-repetitious strains of Pseudomonas aeruginosa isolated from samples of patients hospitalized by not less than 72 hours were studied. The used antibiograms were diffusion in agar (Kirby Bauer's method) and the minimal inhibitory concentration (MIC) were determined through the technique of the E-test. Finally, the antibiophenotypes of Pseudomonas aeruginosa for the betalactams were and classified. The results show that 41.1% of strains of Pseudomonas aeruginosa was sensitive to Ticarcilin, while 605 of the strains was sensitive to Piperacilin (alone and in association with Tazobactam). Ceftazidime has a higher a...