An automatic homing mechanism for a multi-sectional slide includes a sliding block and a hooking member, or further includes a locating member of an inner rail operating in conjunction with an outer rail and a middle rail. The middle rail passes and slides on the outer rail. The sliding block is inserted and slides in a sliding holder disposed at the end of the outer rail. The sliding block is pulled back to the end of the outer rail by way of a first elastic member. A sliding channel of the sliding holder is provided with locating cuts for the sliding block to be relatively secured in position. The hooking member is pivotally connected to the middle rail corresponding in position to the sliding block and includes two hooks to hold against the sliding block by way of a second elastic member. The locating member of the inner rail is pivotally connected to the middle rail to hold against the inner rail by way of a corresponding hook.