Human placental extract is used in the treatment of skin wrinkles and wounds. To date, no studies have evaluated the effects of placental extract on dermal fibroblast proliferation. To investigate the effects of placental extract versus ascorbic acid on fibroblast proliferation and transforming growth factor (TGF)-beta1 expression, cultured human fibroblasts were treated with placental extract (0, 0.08, 0.16, 0.32, and 0.64%) or L-ascorbic acid-2-phosphate magnesium (0, 0.01, 0.1, 1.0, and 10 mM). Fibroblast proliferation was determined by MTT assay, and TGF-beta1 protein expression was analyzed by ELISA. The proliferation of fibroblasts increased significantly after treatment with placental extract at concentrations of 0.32 and 0.64% and with L-ascorbic acid-2-phosphate magnesium at concentrations of 1.0 and 10 mM. Placental extract demonstrated no significant effects on TGF-beta1 expression; however, TGF-beta1 expression significantly increased after treatment with ascorbic acid at concentrations of 1.0 and 10 mM. Placental extract and ascorbic acid had similar effects on fibroblast proliferation; however, placental extract did not significantly increase TGF-beta1 protein expression.