The purpose of this study is the development of the device which presents the information by modulated vibration on the tactile sense. However, there has been no study that tried to the evaluation of cognition to the modulated vibration on the tactile sense. In this paper, the effectivevaluation method of the vital reaction on the discrimination task of the modulated vibration stimuli was proposed, which based on both the Event Related Potential as a physiological index and psychophysical quantity. As a result, the proposed method was effective for quantitatively evaluation on discrimination of modulated vibration, and the efficiency of the evaluation work was improved approximately 50%.