A mechanism for supporting a head carriage provided with a magnetic head to magnetically record still image information or the like into a magnetic disc or reproduce such information therefrom. In the support mechanism, the two ends of a lead screw having a threaded portion almost in the center portion thereof are respectively received by two bearings each having two, substantially perpendicularly intersecting surfaces, and the head carriage, which can be guided and moved by the lead screw, is also provided with two, substantially perpendicularly intersecting surfaces touchable with a shaft of the lead screw. By energizing the head carriage in a given direction by a spring, the head carriage's two intersecting surfaces can be brought into contact with the lead screw, and the lead screw can be brought into contact with the intersecting surfaces of the respective bearings.