The invention discloses a process for treating the surface of a cutting tooth by injecting plasmas. The process comprises the following steps: a, putting the cutting tooth to be treated into an ultrasonic washing agent to be subjected to ultrasonic washing for more than one time; b, putting the cutting tooth which is subjected to the ultrasonic washing into a vacuum chamber; c, releasing pulsed bias; d, introducing mixed gas containing N2, Ar and C2H2 into the vacuum chamber and releasing the pulsed bias; and e, recovering the vacuum chamber to normal pressure and cooling so as to finish the treatment. With the adoption of the process, the wear resisting performance of the surface of the cutting tooth can be effectively improved so that the abrasion degree of the cutting tooth is reduced in a movement process, and the working efficiency is improved and the service time is prolonged.