Background: Conspicuous facial pores are therapeutic targets for cosmeceuticals. Here we examine the effect of topical fullerene on conspicuous facial pores using a new image analyser called the VISIA(R) system. Ten healthy Japanese females participated in this study, and they received applications of 1% fullerene lotion to the face twice a day for 8 weeks.FindingsFullerene lotion significantly decreased conspicuous pores by 17.6% (p < 0.05, Wilcoxon signed-rank test) after an 8-week treatment. A self-administered questionnaire indicated that this reduction achieved cosmetically appreciable effects. In addition, to investigate the mechanism of effect of fullerene, we examined its effect on UVB-induced prostaglandin E2 (PGE2) production in reconstructed human epidermis (RhE). The results showed that irradiation of RhE with 1000 mJ/cm2 increased PGE2 production by 62.3% (p < 0.05, Mann-Whitney U-test) and the addition of 28 muM fullerene significantly suppressed the UVB-induced PGE2 production by 18.3% (p < 0.05). Conclusions: Fullerene lotion significantly decreases conspicuous facial pores after an 8-week treatment possibly through the suppression of PGE2 production in the epidermis.