A strimmer head (10) comprising a cylindrical casing (13) provided with at least a diametrically-opposite pair of holes (14, 15) for entry and exit of a cutting wire (16), and a reel (20) located internally of the casing (13), which reel (20) can be rotated with respect to the casing (13), in which the reel (20) comprises a pair of flanges (21, 22) between which flanges (21, 22) a wall (23) is interposed in order to define, in cooperation with the flanges (21, 22), annular spaces (24, 25) each destined to wind a half of the wire (16). The wall (23) exhibits a wire guide channel comprising two portions (17, 28), being an entry portion and an exit portion for the wire (16), which portions (27, 28) are arranged in directions which do not pass through an axis of rotation of the reel (20).
