Abstract: A thickness adjuster for an ice shaver includes a flat plate to receive an ice block, a movable gear vertically combined with the flat plate to raise it up and lower it down to adjust the height between the bottom of the ice block and a blade so that shaved tiny ice pieces by the blade may be very fine or very rough. The movable gear is combined with a connecting member and then is engaging a transmitting disc gear also engaging a engaing gear portion or a revolvable adjusting disc, the revolvable adjusting disc being rotated to raise up and lower down the falt plate via the transmitting disc gear and the movable gear.