A composite structure includes a first layer and a second layer that are stacked, the first layer is configured to connect the second layer and a flexible display, and the second layer is configured to dissipate heat. Each of the first layer and the second layer includes a first surface and a second surface opposite to each other, where the first surface of the first layer is proximate to the flexible display, and the first surface of the second layer is proximate to the second surface of the first layer. An elastic modulus of the first layer is greater than or equal to an elastic modulus of the second layer, and a coefficient of thermal conductivity of the first layer is less than or equal to a coefficient of thermal conductivity of the second layer.