A fixing mechanism includes a base, a supporter, a torsional component, an actuating component and a resilient component. The supporter is rotatably disposed on the base. The torsional component is disposed on the base and has a first engaging portion. The actuating component is disposed on the supporter and is further movably switched between a first position and a second position. The actuating component has a second engaging portion. The actuating component moves from the first position to the second position to engage the second engaging portion with the first engaging portion. Two ends of the resilient component are respectively connected to the supporter and the base. When the second engaging portion is disengaged from the first engaging portion, the resilient component rotates the supporter relative to the base. A rotary angle between the supporter and the base is fixed by the torsional component via the actuating component.