Observations were made on 252 patients with imported malaria during 1963 to 1971. The majority of the patients came from the countries of Africa. Predominance of tropical malaria and also cases of ovale malaria previously not recorded on the territory of the Soviet Union were noted. As a result of early hospitalization and treatment the course of the disease was short in most of the patients and was accompanied by a slight enlargement of the liver and spleen, and a mild anemia; a normal ESR was seen in 52.8% of the patients. Ovale malaria (36 patients) was characterized by the appearance of paroxysms in the evening, and a regular 3 day intermittent fever beginning from the onset of the disease; spontaneous cessation of paroxysms occurred in 3 patients. An extremely potent schizontocidal action of 4 aminoquinoline was noted; temperature normalization occurred in 2 days in 94% of the patients. Use of quinocide ensured radical curing of a 3 day malaria after 1 course of treatment.