The present application discloses a method for fabricating a flexible display device, a flexible display device and a display apparatus, the method including: disposing a separation layer on a surface of a substrate; disposing a flexible substrate on a surface of the separation layer away from the substrate; disposing a display assembly on a surface of the flexible substrate away from the separation layer; separating the flexible substrate from the separation layer to obtain the flexible display device; wherein an adhesion between the flexible substrate and the surface of the substrate is greater than an adhesion between the separation layer and the surface of the flexible substrate, an adhesion between the separation layer and the surface of the substrate is greater than the adhesion between the separation layer and the surface of the flexible substrate. By the above method, the application can increase the yield of the flexible display device.