A sliding assistance mechanism for helping a switching operation of a moving body on a main body side from a first position to a second position, or from the second position to the first position, includes a case 1 attached to the main body side; first and second moving members (sliders 2A, 2B) slidably placed in the case 1, respectively; a pair of latches 5, 5 pivotally supported at each moving member, respectively, and releasably locked to corresponding parts of a case side; and an urging device 3 provided between both moving members. When the moving members are halfway switched to the first position from the second position, or to the second position from the first position, an engagement of one of the latches is released by an engagement pin 9 additionally provided in the moving body, and the engagement pins are pulled with the latch into the first position or the second position with an approaching drive through the moving members and the urging device 3 to a side of the other latch.