For a long time ornithosis has been considered an occupational disease, while the significance of sporadic (home) forms of the illness has been underestimated due to difficult clinical diagnostics which results from polymorphic clinical manifestations and the absence of appropriate epidemiological data in home cases of the disease. Sporadic ornithosis (psittacosis) is a pathology which is spread widely enough and whose diagnosis is very difficult. One of the most typical manifestations is pulmonary lesion resulting in dysfunction of external respiration. Difficulties with diagnosis of psittacosis are caused by the rarity of the disease and the lack of attention to the epidemiological method (epidemiological anamnesis) among non-infectionists; late diagnosis results in long treatment. This report contains data from complex clinico-laboratory examination of patients with sporadic psittacosis using immunological techniques (indirect hemagglutination reaction is an effective serological test for diagnostics of ornithosis).