The invention provides a method of making a flexible display and a substrate for making a flexible display. The method includes the following steps: providing a rigid substrate; forming a sacrificiallayer on the rigid substrate; coating the sacrificial layer with a polymer material to form a flexible substrate, wherein the sacrificial layer is sticky so the flexible the substrate can be adhered to the rigid substrate through the sacrificial layer; making a display element layer on the flexible substrate; and volatilizing the sacrificial layer by reducing the intensity of pressure, in order toseparate the flexible substrate from the rigid substrate. According to the method of making a flexible display and a substrate for making a flexible display, no damage is caused to a flexible display, and the making process is simplified. Moreover, the sacrificial layer after volatilization is collected and liquefied and then reused, the cost is greatly saved, and a flexible display of high quality can be obtained.