A spoke fastening device includes a spoke fastening hole drilled through a spoke bed of a wheel rim for receiving a head and a stem of a nipple and a collar of a ferrule, the collar includes an inner peripheral wall and an outer peripheral wall each having a lower portion for engaging into the spoke fastening hole of the spoke bed, the inner peripheral wall includes an outwardly curved rim for engaging with the spoke bed of the wheel rim, and the outer peripheral wall of the collar includes another outwardly curved rim for engaging with the curved rim of the inner peripheral wall, the head of the nipple flares and deforms the lower portions of the peripheral walls to engage with the spoke bed of the wheel rim.