A urine-collecting device comprising a urine-collecting bag having an opening for inserting a penis therethrough, the opening being made on one side surface of the bag and a sheet-like flange formed integrally with the bag at a periphery of the opening; and a film for preventing a back flow of urine having a hole with a diameter being smaller than that of the opening, characterized in that the film is formed to be cap-shaped and is put on the flange to elastically cover the flange.According to a device of the present invention, the device is applicable to any kind of patient, does not either cause a feeling of physical disorder or injure a penis, enables a bedridden old man or sick person to urinate while lying in order to be convenient for care thereof, and can be used sanitarily without causing a leak of urine.