A string twisting head device, comprising a twisting mechanism (1) and a string crossing and looping mechanism (4). The twisting mechanism (1) comprises a twisting head assembly (11); the twisting head assembly (11) comprises a twisting rod (111) and a string hanging pin (113); the string crossing and looping mechanism (4) comprises a crossing and looping head (42); a looping rod (45) is provided on the crossing and looping head (42); a string bearing inclined surface (A1) is provided at a front end portion of the twisting rod (111); the string hanging pin (113) is provided in the string bearing inclined surface (A1); a protruding inclined stepped surface (A2) is provided at the part of the string bearing inclined surface (A1) close to a string line (X); a side vertical surface (A3) is provided at the high end of the inclined stepped surface (A2); after the looping head (42) is lowered and abuts against the string line (X), the bottom surface of the looping head (42), the side vertical surface (A3) at the high end of the inclined stepped surface (A2), the string bearing inclined surface (A1), and the outer circumferential surface of the string hanging pin (113) form a closed space surrounded on four sides; the string line (X) is confined inside the closed space. A string automatic processing apparatus using the string twisting head device. The device can improve the precision and the efficiency of string twisting, thereby improving the yield and the stability of the string.