The invention provides a composite flexible door. The composite flexible door comprises a cross beam, two steel wire gauzes, a filling layer and flexible door surface layers. The cross beam comprisesan upper beam body and a lower beam body. The upper beam body is in a columnar shape with the bottom being provided with a mounting groove, and a rectangular hole is formed downwards in the surface ofthe lower beam body. The two steel wire gauzes are arranged on the two sides of the upper beam body correspondingly, and enable the upper beam body to be connected with the lower beam body. The filling layer comprises two fiber layers, an aerogel layer and a filling material. The two fiber layers are attached to the inner sides of the two steel wire gauzes correspondingly, the aerogel layer is arranged between the two fiber layers and evenly provided with filling holes; the filling material is granular and the filling holes are filled with the filling material; and the flexible door surface layers are attached to the outer sides of the two steel wire gauzes. The composite flexible door has excellent fire resistance, heat preservation and mechanical properties while the certain flexibilityis ensured, and can be suitable for various kinds of working environments and is higher in practicality.