The effect of Amaranthus cruentus L. seed oil (AmO) on collagen biosynthesis and wound healing was studied in cultured human dermal fibroblasts exposed to UVA radiation. It has been found that UVA radiation inhibited collagen biosynthesis, prolidase activity, expression of β1-integrin receptor, phosphorylated ERK1/2 and TGF-β, while increased the expression of p38 kinase. The AmO at 0.05-0.15% counteracted the above effects induced by UVA radiation in fibroblasts. UVA radiation also induced the expression and nuclear translocation of pro-inflammatory NF-κB fac-tor and enhanced the COX-2 expression. AmO effectively suppressed the expression of these pro-inflammatory factors induced by UVA radiation. Expressions of β1 integrin and IGF-I re-ceptors were decreased in the fibroblasts exposed to UVA radiation, while AmO counteracted the effects. Furthermore, AmO stimulated fibroblast’s migration in a wound healing model, thus facilitating the repair process following exposure of fibroblasts to UVA radiation. This data suggest the potential of AmO to counteract UVA-induced skin damage.