A hinge mechanism is provided, including a rotary member, a first member, a second member, a first shaft, and a first slider. The first member has a first guiding channel. The second member pivotally connects to the first member and has a first recess. The first shaft pivotally connects the rotary member and the first member, wherein the first shaft has a first cavity. The first slider is movable between the first recess and the first cavity. When the first slider is located in the first recess, the first member is prohibited from rotating relative to the second member by the first slider. When the first slider slides from the first recess along the first guiding channel to the first cavity, the rotary member is prohibited from rotating relative to the first member by the first slider.