In this paper, the vibration suppression of torsional vibrating system is investigated through the delayed vibration absorber of neutral type. The stability theory of dynamic system was applied to study the stability of the neutral delayed vibration absorber and the torsional vibrating system, and their stable regions were obtained, respectively, by taking time delay as a parameter. Moreover, The absorbing effect of dynamic vibration absorber with the delay changing was obtained. It is shown that the stable region of the vibration absorber and vibration reduction system became larger when compared with the general delayed vibration absorber. Finally, the numerical simulations were also carried out to verify the analytic results.