The present invention solves the issue of bacterial infection by medical devices such as intracorporeal indwelling catheters. The present invention relates to an ultrasonic medical apparatus including a medical device (titanium oxide coated medical device 10) covered with a titanium oxide material (titanium oxide alone or a titanium oxide composite material) and ultrasonic irradiation means 20. Ultrasonic irradiation of the titanium oxide material, which exists on a surface of the medical device, causes the surface of the medical device to exert beneficial effects such as antibiotic action, the stimulation of angiogenesis, and the degradation of a blood clot and a biofilm.