PURPOSE: To further enhance polishing efficiency in an oscillating type polishing device for oscillating a tank in which an abrasive and a material to be polished are received to polish the material.

CONSTITUTION: An oscillating driving means for reciprocating and oscillating a tank 3 is formed of a heart cam 16 rotated by a driving motor 15, a driving lever 18 having one end pivotally supported and the middle part engaged with the heart cam 16 and oscillated, a sector gear 10 reciprocating and rotating in linkage with the oscillation of the tank 3, an oscillating arm 10 extended from the sector gear 10, and a link 20 having one end connected to the other end of the driving lever 18 and the other end connected to the osculating arm 11 in such a manner as to be capable of regulating the position. Further, the tank 3 is oscillated almost at an equal speed by use of the heart cam 16 to provide marvelous stirring and fluidizing effects on the material in the tank 3, and a higher polishing efficiency is provided.