Device-independent quantum key distribution protocol is one of the most important research directions in the field of quantum information theory in recent years. The security of this kind of protocolsis not based on the perfect state preparation and measurement, thus it can be applied to avoid the blinding attack from intense light and the wavelength attack, which leads to higher security. Device-independent quantum key distribution protocols are based on the Bell inequality, and the classical value violation can be used to guarantee the security. Based on α_CHSH inequality, the security of device-independent quantum key distribution protocols is investigated in the bit flipped channel model,and the relationship between the final secret key rate with the violation value of α_CHSH inequality is given.