The invention belongs to the technical field of armored vehicle matched articles, and particularly relates to a periscopic window door particularly suitable for a caterpillar or wheel type armored vehicle. According to the periscopic window door, steel balls are installed in corresponding hemispherical sliding track grooves formed between an inner side door body and an outer side door body, and therefore a window door rotating mechanism with a 360-degree all-dimensional rotation function is achieved; an observation device is arranged on the window door, and therefore a passenger can conveniently conduct outward periscopic observation by the use of the observation device which rotates along with the window door; a search lamp and the observation device are combined with each other, and therefore the consistency of the observation direction and the lighting direction can be achieved, and the night viewing capacity is improved; and by means of a power assisting device with a torsion bar structure, the window door can be opened more easily and more conveniently.