The authors have studied the morpho-biochemical properties and the sensibility at antimicrobial drugs, of specie of Pseudomonas, the Pseudomonas maltophilia, (Hugh & Ryschenkow, 1960), isolated from vaginal secretion. Since important characteristics among more of sixty-five tested, the strains studied show to be: oxidase negative and lysine decarboxylase positive; to present deoxyrononuclease activity and produced a diffusible brown pigment: acid was produced by oxidation of maltose as much in nitrogenous complex medium as in Hugh & Leifson medium and they hydrolise the esculin. the strains was sensible, for the colistin chloranfenicol, gabromycin, gentamycin and nalidix acid.