Disclosed is a leaf positioning device (100) for a multi-leaf collimator, comprising: a transmitting plate (110), a receiving plate (120) and a positioning module (130), wherein the transmitting plate (110) and the receiving plate (120) are oppositely provided on a leaf guide rail box (101) of a multi-leaf collimator； a plurality of positioning signal transmitters (111) are provided on the transmitting plate (110)； a plurality of positioning signal receivers (121) are correspondingly provided on the receiving plate (120)； leaves (108) of the multi-leaf collimator are provided between opposing positioning signal transmitters (111) and positioning signal receivers (121)； a positioning signal transmitting path of the positioning signal transmitters (111) is parallel with a plane formed by the movement of the leaves (108) of the multi-leaf collimator； and the positioning module (130) is connected to each positioning signal receiver (121) so as to receive an output signal of the positioning signal transmitters (111). The present technical solution can position the position of each leaf (108) of a multi-leaf collimator, directly reading the position where each leaf (108) is currently located, and cooperating with a screw (105) to precisely control the movement of the leaves (108).La présente invention concerne un dispositif de positionnement de lame (100) destiné à un collimateur multi-lame, comprenant : une plaque de transmission (110), une plaque de réception (120) et un module de positionnement (130), la plaque de transmission (110) et la plaque de réception (120) étant disposées de manière opposée sur une boîte de rail de guidage de lame (101) d'un collimateur multi-lame ； une pluralité de transmetteurs de signaux de positionnement (111) sont disposés sur la plaque de transmission (110) ； une pluralité de récepteurs de signaux de positionnement (121) sont disposés de manière correspondante sur la plaque de réception (120) ； les lames (108) du collimateur multi-lame so
