Computers may be designed to regularly observe one’s emotion and respond intelligently to his/ her negative emotion such as stress, fatigue, boredom, and etc. This certainly requires quantification of human emotion and this study aims to find out the parameters that may be useful to differentiate one’s emotion. In this study, human emotion was artificially induced by having 26 undergraduate students exposed to four different types of emotion-evoking sounds and smells. Then the participants were asked to rate subjectively their emotion that was later categorized into one of the four quadrants made up by pleasantness vs. unpleasantness and arousal vs. relaxation. Physiological changes in EEG (F3, F4, P3, and P4), EDA, ECG and skin temperature were recorded and analyzed to differentiate among two dimensional emotions. As a result, a number of physiological measures were found in this study to successfully classify two dimensional emotions.