Studies that evaluate human emotions from biological signals have been actively conducted, with many using images or sounds to induce emotions passively. However, few studies utilized the action of working to elicit emotions (especially positive ones) actively. Hence, in this study, emotions were examined during working (a puzzle was used in this study) from the psychological viewpoint of the Profile of Mood States 2nd Edition and the physiological viewpoint of electroencephalograms (EEGs). As a result, different time-dependent changes of power change rate in the theta band in the frontal region were observed between the presence and absence of the emotion "fatigue-inertia." Those in the alpha band in the frontal region were observed between the existence and nonexistence of the emotion "vigor-activity." Therefore, it is suggested that we can evaluate the emotion of a subject while working by a spatiotemporal pattern of band power obtained by EEG.