A flexible display device (10) is disclosed. The flexible display device comprises a flexible substrate (12), a number of display pixels (14) arranged in a form of rows and columns on the surface of the substrate, a number of grooves (16) in the surface of the substrate each of which is formed in between adjacent two rows or columns of the display pixels (14), and connection lines (18) for electrically interconnecting the plurality of display pixels (14), thereby providing flexibility to the display device and, at the same time, minimizing the propagation of mechanical stress caused when the display device is bent or rolled. A method of manufacturing the display device is also disclosed.