Pattern reversal visual evoked potentials (Pr- VEP) playas a routine part of diagnosis, prognosis, monitoring and evaluation tool of patients with pituitary tumor was proposed in many researches. In this study, the authors applied Pr-VEP technique to record VEP for 21 patients with computerized tomographically documented pituitary tumor. The result indicated that VEP morphology, rate of VEP waves, amplitudes and interpeak latency did not difference with those of normal people. However, significantly prolonged of VEP wave latencies was found in patient with pituitary tumor compared to norm people (p0.05). With this result, the authors confirm that Pr-VEP is suitable for all cases alleged to be pituitary tumor.