Provided are a medical device, and a fixing mechanism for a medical apparatus of the medical device. With the fixing mechanism, a medical apparatus can be conveniently positioned at a target position in a body to allow the medical apparatus to achieve a corresponding implantation or interventional treatment, thereby improving a medical treatment effect. The medical apparatus may be a leadless pacemaker, which facilitates better physiological pacing of the heart by means of the pacemaker. The fixing mechanism comprises a base (1), and a fixing piece (4), wherein the direction in which the base (1) extends is parallel to the direction in which a predetermined object extends, the fixing piece (4) is arranged on an outer wall of the base (1) and extends around the base (1), one end of the fixing piece (4) is connected to the outer wall of the base (1), and a clearance is formed between the other end of the fixing piece and the outer wall of the base (1). In actual use, the base (1) is subjected to a force to rotate in the direction in which the fixing piece (4) extends and drives the fixing piece (4) to also rotate together with same, and during rotation, the fixing piece (4) is directly inserted in tissue or a blood vessel wall which is parallel to the base (1), thereby allowing the medical apparatus to be fixed in the atrium (12), a ventricle, the superior vena cava (14) or other blood vessels, and to also be fixed on an interventricular septum part (15) or an interatrial septum part.La présente invention concerne un dispositif médical et un mécanisme de fixation pour un appareil médical du dispositif médical. Avec le mécanisme de fixation, un appareil médical peut être facilement positionné à un emplacement cible dans un corps pour permettre à l'appareil médical d'effectuer un traitement d'implantation ou d'intervention correspondant, améliorant ainsi un effet de traitement médical. L'appareil médical peut être un stimulateur cardiaque sans fil, ce qui facilite une m
