The invention discloses a sugar coating mechanism for a spherical fruit bottom sugar-coating machine. The sugar coating mechanism comprises a main box body, wherein a plurality of support legs are fixed at the bottom of a base plate of the main box body; a drive screw and a guide rod are arranged on the upper part of the main box body; the two ends of the drive screw and the guide rod are both hinged on two lateral plates of the main box body; a driving motor is fixed on an outer side wall of one lateral plate of the main box body; an output shaft of the driving motor is arranged as a spline shaft; the spline shaft is inserted into a spline hole at one end of the corresponding drive screw in a sleeved manner; a moveable block is screwed in the drive screw; the guide rod is inserted into the moveable block in a sleeved manner; a clamping mechanism is fixed at the bottom of the moveable block. The sugar coating mechanism can be used for clamping the spherical fruit and coating the liquid sugar and has high efficiency and good effect.