Laquer tree (Rhus verniciflua Stokes; Anacardiaceae, RVS) has been used in oriental medicines. This study examined whether the extract of RVS free of urushiol (detoxified RVS extract, DRE) exerting anti-inflammation could alleviate the symptoms of atopic dermatitis (AD) induced with 2,4-dinitrochlorobenzene (DNCB) in NC/Nga mice. DRE contained flavonoids like fustin (153 mg/g), fisetin (14.6 mg/g), sulfuretin (13.3 mg/g), and quercetin (0.95 mg/g). DRE (10 ${mu}g/mL$) decreased the production of nitric oxide activated by lipopolysaccharide. Oral administration of DRE (200 mg/kg weight/day) decreased scratching frequencies, the epidermal thickness on dorsal skin, and the number of degranulated mast cell. DRE significantly lowered the levels of IgE in sera (p<0.01), which were elevated by DNCB. DNCB reciprocally raised IL-4 and lowered IFN-${gamma}$ in media of spleenocyte. DRE reversely raised IFN-${gamma}$ and lowered IL-4. Contrastively, dexamethasone suppressed the overall immune reactions. In conclusion, DRE inhibited Th2-mediated IgE overproduction through modulation of Th1/2 balance, which was in part attributed to anti-inflammatory activity.