A X-structure of a key and a manufacturing method thereof are disclosed. The X-structure comprises a first frame and a second frame. The first frame comprises a bar. The first frame is connected and pivoted to the second frame via a fold located on the bar. The key comprises a keycap, a base and the X-structure installed between the keycap and the base. The manufacturing method of the X-structure comprises: providing the X-structure and pressing the bar to generate a fold until the first engaging portions are connected and pivoted to the second engaging portions.