To provide a decorating device which does not take an inappropriate action.

The rotary decorating device for decorating tiles is equipped with a movable plane for installing tiles, a movable surface on which the tiles are conveyed in a predetermined advancing direction, a decorating part including a plurality of cylinders arranged over the movable surface, and a rotating means for rotating the cylinders around the axis line. One of the cylinders is rocked against the other cylinders. The rotating means for the cylinders has a mechanical drive transmission part including a plurality of driven gears, and these driven gears are concentrically and firmly associated with each of the cylinders. The driven gears are coupled and rotated by a driving member without following a relative drag, and the diameters of the driven gears are different from the diameters of the cylinders which constrain the driven gears. A relative position between any two cylinders out of the cylinders can be adjusted in a predetermined direction corresponding to the advancing direction on the movable surface. An angle arrangement can be adjusted by just moving one of the cylinders against the others.