Provided is a flexible display device, including a flexible display panel and a support structure, the flexible display panel includes a main structure region, a bending region and an extension region, the bending region is bent to locate the extension region at a back of the main structure region, an accommodation space is formed between the main structure region, the extension region and the bending region, at least part of the support structure is located in the accommodation space, and one end of the support structure extends into a bending space surrounded by the bending region.