This paper presents experimental results of a study the influence of nonlinear effects on the range of the phase-sensitive optical time-domain reflectometer. Results from measurements of the impact of the effects of stimulated Raman scattering, stimulated Brillouin scattering, self-phase modulation, and modulation instability are presented. It is shown that the power of the probe pulse for 200 ns does not exceed ≈300 mW.