Lophomonas sp. is a habitual parasite of the intestinal tract of the cockroaches and that is not recognized as pathogenic human being. Nevertheless, in the world literature are few reports of Lophomonas sp. in respiratory tract secretions in patients with severe pulmonary disease, mostly in adults. We present evidences of Lophomonas sp. in the respiratory low tract of children attended in the national reference center of paediatric diseases of Lima, Peru, in the period 2009-2010. We found six cases, 4/23 from broncoalveolar lavage and 2/794 from tracheal aspirate samples of children. Five of them had pneumonia and one atelectasis, four were hospitalized in the intensive care unit. Increase knowledge about the presence of this organism in respiratory infections is needed, as its real pathogenic role.