A reversible ratchet mechanism comprises a cylindrical head (10) having axially a center hole in which the cylindrical body (22) of a torsion transmitting element (20) is rotatably disposed. The cylindrical body is provided axially with a V-shaped slot (23) in which a V-shaped pawl (30) is fastened pivotally such that two arms (32a,32b) of the V-shaped pawl form an angle smaller than the V-shaped slot. Two arms of the pawl are provided respectively on the top end thereof with an plurality of pawl teeth (31a,31b) engageable with a plurality of axial teeth (101) provided on an inner wall surface of the center hole of the cylindrical head. Fastened pivotally to the cylindrical body is a round rod (40) which is located between the two arms of the pawl and is provided at the midsegment thereof with a spring-biased pin (41) capable of urging either one of the two arms of the pawl depending on the angular position of the round rod, thereby resulting in the engagement of the pawl teeth with the axial teeth of the center hole of the cylindrical head. <IMAGE>
