The volatile oil extraction yield of the different parts in Gongju was compared and extraction process from fresh leaves was optimized.The volatile oil was extracted by water distillation from roots,stems,leaves,flowers and dried leaves,dried flowers of fresh Gongju.The extracting conditions from fresh leaves were optimized by orthogonal design.It showed that the extraction yield from fresh leaves was the highest,there was no significant variation in volatile oil yield from fresh leaves when pH valued at 5~9,the extraction yield was affected by particle size,soaking time,solid-liquid ratio,distillation time.The optimum extraction conditions were : particle size 4mm,soaking time 12 h,solid-liquid ratio 1∶3,the distillation time 4 h,the extraction yield 0.0020 mL/g.The optimum extraction process was stable and feasible.The results shows that the study of deep processing of Gongju leaves is necessary and it may have good application in medical and health products industries.