The utility model discloses a pumping unit brake hub fastening device, and belongs to the field of oil exploitation. The device comprises a screw rod (100), a first inner clamp (200) and a second inner clamp (300), wherein a fixing piece (110) is arranged at the first end of the screw rod (100); the first inner clamp (200) and the second inner clamp (300) are arranged on the screw (100) in a sleeving mode. wherein the first inner clamp (200) is located between the second inner clamp (300) and the fixing piece (110), the first inner clamp (200) and the second inner clamp (300) are used for being clamped on the outer wall of an oil pumping unit brake hub in an oil pumping unit brake device, and the screw (100) is used for moving the second inner clamp (300) in the direction close to the first inner clamp (200). According to the oil pumping unit brake hub fastening device, the fastening process of the oil pumping unit brake hub is simple, convenient, rapid and efficient, time and labor are saved, and meanwhile the good fastening effect can be guaranteed.