Abstract:The yield of camptothecin (CPT) accumulated in two strains of Camptotheca acuminata Decne, i.e. Sichuan (SC) strain and Hisun-Ⅰ(HI) strain, were compared in filed condition using HPLC method. The results showed that the content of CPT, biomass accumulation and consequent CPT yields in H1 were significantly higher than those in SC strain. With regard to H1 strain, the content of CPT in the upper branches and leaves was much higher than those in the middle and bottom parts, while the yield was significantly reverse because of the low biomass. In June, the H1 strain contained more CPT in leaves than in other months. However, the biomass accumulation in June was comparatively lower. For the continuous yield purpose, the branches and leaves on the upper part was suggested to be harvested in June. However, the middle and bottom parts were harvested from July to October, and one third of which on the bottom part was harvested in November, the end of the growing season.