Kyungohkgo (KOG) is an oriental herbal medicine that has been used for its various pharmacological effects, which include anti-oxidant, anti-inflammatory and immuno-regulation activities. But its effects and mechanisms of anti-atopic dermatitis (AD) have not been elucidated. HaCaT cells were pre-treated with KOG for 1 h and stimulated with tumor necrosis factor (TNF)-α and interferon (IFN)-γ (10 ng/ml each). After 24 h, cells were harvested to measure the production of reactive oxygen species (ROS) and chemokines such as regulated upon activation, normal T cell expressed and secreted (RANTES/CCL5), Thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-deraived chemokine (MDC/CCL22). To investigate the regulatory mechanisms of KOG, we also assessed the phosphorylation of signal transducer and activator of transcription (STAT1) signaling pathways in HaCaT cells. Treatment of KOG decreased the ROS production and mRNA levels of RANTES, TARC, MDC with a concentration dependent manner. In addition, KOG significantly inhibited TNF-α and IFN-γ induced phosphorylation of STAT1. This could indicate that the KOG shows anti-AD activity mainly through STAT1. Thus, we propose that KOG may be a promising anti-AD skin protector, which could suggest the clinical basis for cosmetics development.