A pneumatic display device, comprising a plate block embodying a plurality of superimposed transparent plates, each of these plates being provided with means defining a disc guide channel. Each disc guide channel has a first air channel followed by a supply section for a plurality of non-transparent display discs displaceably arranged in a row therein, a display section following such supply section, said display section being in the form of a trace line for symbolizing a character at the region of a display zone limited by a display window provided at a nontransparent cover plate of the plate block. At the end of the display section such merges into a second air channel. Upon blowing air into the first air channel of a preselected plate the display discs thereof are displaced out of the supply section thereof into the display section thereof and thereby become visible at the display zone in the form of a desired character and upon further blowing air into the second air channel these display discs are again forced back into the supply section of the relevant disc guide channel.