The invention provides an insulation board shape cutting device and a use method thereof. The insulation board shape cutting device comprises an operating platform, an operating bracket and a cutting lead. The operating bracket comprises a fixed bracket and a movable bracket. The fixed bracket is mounted on the operating platform; and the movable bracket can move relative to the fixed bracket. The cutting lead is arranged on the movable bracket of the operating bracket. The insulation board shape cutting device can be used for simply and effectively cutting an insulation layer; moreover, the plane cut by the insulation board shape cutting device is evener.