The invention relates to a thin-shaped display device and an electronic paper display picture control method thereof. The thin-shaped display device comprises an electronic paper, a bent sensor and a processing unit, wherein the electronic paper is provided with a display surface and a back surface contrary to the display surface; the bent sensor is arranged on the back surface of the electronic paper; the processing unit is respectively electrically connected with the bent sensor and the electronic paper; the bent sensor is used for sensing a way of bending the electronic paper and correspondingly generating an electrical signal; and the processing unit shrinks or amplifies the display content of the display surface of the electronic paper according to the electrical signal. The invention enables a user to bend the electronic paper in a very instinct way by utilizing the characteristic of the electronic paper capable of being bent, thereby achieving the purpose of controlling the reduction or the amplification of a picture of the electronic paper.