PURPOSE: To reduce the overall side of the structure of a disk player by forming guide grooves in cam plates, provided an upward and downward moving mechanism, horizontally at upper and lower parts.

CONSTITUTION: This mechanism consists of an opening device 15 which makes it easy to extract a video disk 4 and a lid plate 6 by the opening part 7 of a jacket 5, a disk receiving table 16, an upward and downward moving device 17, a chucking device 18, and a driving devide 19. When an upward and downward sliding plate 42 moves as shown by an arrow B or C, an upward and downward moving table 45 moves as shown by the arrow B or C with slider hooks 48 and 48 engaged in the grooves 47 and 47 of cam plates 46 and 46 and its movement direction is restricted by engagements between guide grooves 54, 54 and 54, and guide pins 55, 55 and 55, so that the table 45 moves up or down. Further, the grooves 54, 54 and 54 made in the cam plates 46, 46 and 46a are formed horizontally at upper and lower parts, and the intermediate parts of the grooves 54, 54 and 54 slant, so that the stroke of unnecessary upward and downward movement is absorbed.