A keyboard includes an upper frame, a main body, a lower frame, and an adjustment mechanism. The two frames cooperate with each other to sandwich the main body. The lower frame includes a bottom plate defining a though hole. The adjustment mechanism is configured to adjust an inclined angle of the keyboard, and includes an adjustment member, a supporting member, a driving member and a position stopper. The adjustment member is operated by a user. The supporting member protrudes from the bottom plate via the through hole to support the keyboard on a supporting surface. The driving member drives the supporting member to move along a central axis of the through hole to adjust a protruding distance of the supporting member when the adjustment member is operated. The position stopper resists the supporting member to secure the supporting member when the adjustment member is free.