The invention provides a portable stool with a function of displaying an advertisement. The portable stool comprises a seat plate, two supporting parts and a display board, wherein the two supportingplates have a plate structure, are parallel and are alternately arranged at the bottom of the seat plate; slots are formed in outside faces of the supporting parts; the supporting parts are detachablyconnected with the seat plate; the display board is inserted into the slots; and a drawing surface is arranged on the back of the supporting plates. According to the portable stool, the seat plate isdetachably connected with the supporting parts, the portable stool with the function of displaying an advertisement can be detached and put into a bag or a box, and can be used by splicing when beingused; the supporting parts adopt a plate structure and are arranged on the seat plate, slots are formed in the outward faces of the supporting parts and are used for assembling the display board, andartistic pictures, advertisements and the like can be drawn on the display board. The portable stool has a taking function, and is convenient to carry after being detached; and furthermore, the display board is especially provided to enable the portable stool to have an advertising function and the like.