Objective: To evaluate the effect of standardized extract of Centella asiatica ECa 233 on inflammatory mediator production through cyclooxygenase-2 (COX-2), extracellular signal-regulated kinase 1/2 (ERK1/2) and nuclear factor-κB (NF-κB) pathway in keratinocyte HaCaT cells.Methods: HaCaT cells were treated with 0.1, 1, 10 and 100 μg/mL ECa 233 in the presence of lipopolysaccharide (LPS). Proinflammatory cytokines and prostaglandin E2 were assessed with ELISA. West blotting was used to determine the inhibition of COX-2, ERK1/2 and NF-κB protein expression. Results: ECa 233 suppressed LPS-induced release of interleukin-1β, tumor necrosis factor-α, and prostaglandin E2. ECa 233 also inhibited COX-2, phosphorylation of ERK1/2 and the activation of NF-κB. Moreover, the formation of reactive oxygen species (ROS) was decreased in response to LPS-inflamed keratinocytes. Conclusions: ECa 233 inhibits LPS-stimulated production of inflammatory mediators in keratinocytes via suppressing ERK1/2 and NF-κB pathways. The suppressive effect of ECa 233 may be related to an inhibition of ROS production.