Disclosed is an intramedullary nail capable of controlling a plurality of engaging members (29, 33), if used, simultaneously with respect to a body. The intramedullary nail includes a rod body inserted into a medulla from one end of an extending bone and having a plurality of through holes (17, 19) intersecting the axis, and a plurality of engaging members (29, 33) individually inserted into the corresponding individual through holes (17, 19) of the body so that they can engage with the bone. Holes (21) are formed to extend from one end of the body to the individual through holes (17, 19). The intramedullary nail is the member which is inserted from the hole (21) and housed in the body inside, and is shaped such that its one end can contact with one of the engaging members (29, 33) and such that it can receive another engaging member. A control mechanism comprises a control member (1) capable of controlling the fixtures of the individual engaging members (29, 33) simultaneously with respect to the body.
