Moringa oleifera Lam. has multiple biological properties that are applicable to developing cosmeceuticals. The objective of this study was to evaluate anti-inflammatory effects of M. oleifera on normal human keratinocytes. The antiinflammatory effects of water extract and 50% ethanol extract of M. oleifera leaves, and of the bioactive compound astragalin, on UVB-irradiated human keratinocytes were investigated. The levels of inflammatory mediators IL-1α, IL-8, NO and PGE2 released from keratinocytes were measured using ELISA and Griess assays. UVB irradiation increased the release of IL-1α, IL-8 and PGE2 into cell culture media after 24 h. The effect was significantly decreased by treatments with astragalin and M. oleifera leaf extracts, of which the 50% ethanol extract showed stronger inhibition than the water extract. These results suggest that this extract is a potential ingredient in products for relieving UVB-induced skin inflammation. Astragalin could be used as a bioactive positive control in the quality control of the extract.