[Objective] To optimize the extraction technology of essential oil from Thuja occidentalis L.[Method] The methods of salting-out and steam distillation were adopted to study the extraction technology and inspect the effect of NaCl concentration,liquid-solid ratio,soaking time and distillation time on the extraction rate of essential oil.[Result] The optimum extraction conditions were:4% NaCl,1:15(g/ml) solid-liquid ratio,6 h soaking time and 3 h distillation time.Under these conditions,the extraction rate was the highest(1.80%).[Conclusion] The method is simple and reliable,which is applicable for industrial production. [Objective] To optimize the extraction technology of essential oil from Thuja occidentalis L. [Method] The methods of salting-out and steam distillation were adopted to study the extraction technology and inspect the effect of NaCl concentration, liquid-solid ratio, soaking time and the distillation time on the extraction rate of essential oil. [Result] The optimum extraction conditions were: 4% NaCl, 1: 15 (g / ml) solid-liquid ratio, 6 h soaking time and 3 h distillation time. , the extraction rate was the highest (1.80%). [Conclusion] The method is simple and reliable, which is applicable for industrial production.