A travel-proofed portable computer keyboard with keys sealed against dust and minor impacts includes an alphanumeric keyboard, a numeric keypad, and a first locking mechanism. The alphanumeric keyboard includes an open cavity. The numeric keypad is received in or protruding from the cavity. The numeric keypad includes a first notch and a second notch. The first locking mechanism includes an engaging member which can lock the numeric keypad in place. The numeric keypad is held in the cavity of the alphanumeric keyboard when the engaging member engages the first notch of the numeric keypad, thereby facilitating the carrying of the computer keyboard. The numeric keypad is held to protrude from the cavity of the alphanumeric keyboard when the engaging member engages the second notch of the numeric keypad, thereby enabling the use of the computer keyboard.