A hair clipper (1) comprises a replaceable blade block (3) having a comb-shaped stationary blade (5) and a comb-shaped moving blade (6) which is reciprocally movable in a widthwise direction of the hair clipper (1), a main body (2) having a motor (8) and a driving member (14) to transfer and to transmit a driving force of the motor (8) to reciprocal motion of the moving blade (6), and to which the blade block (3) is detachably attached, and a pressing mechanism (4) to press the moving blade (6) toward the stationary blade (5). The pressing mechanism (4) is provided on the main body (2) and has at least one contact portion (4b) which reciprocally moves in synchronism with a reciprocal motion of the moving blade (6).