The study presents an investigation of the effects of the recommended office lighting on subjects' mood and cognitive performance in the physical setting of an office. In addition, a gender effect in the performance appraisal task was examined, both as a between- and within-subject factor. The results showed no significant effect of the lighting on the performance of cognitive tasks. However, an interaction between gender and color temperature on mood showed that 3000K (more reddish) and 4000K (more bluish) office lighting may communicate different affective loadings or meanings to each gender. The cognitive workload induced by almost 2 hours of intellectual work diminished the subjects' positive mood and augmented a negative mood. Moreover, independently of their gender, the raters evaluated the neutral female significantly different from the neutral male ratee. Implications of these findings for the mood effects of indoor lighting and the gender effect in work-related judgment are discussed.