Abstract: The endogenous hormones (IAA, ABA, GA3, CYT) content in the root, stem, leaf and the change of root starch content of different starch content of cassava varieties at different periods were studied in order to explore endogenous hormones (IAA, ABA, GA3, CYT) content of cassava and its relation to tuberous root starch accumulation. The main results were showed as follow: the content of IAA in root, stem, leaf were similar which were peaked at the beginning of the root form. High significant and positive correlation between the content of ABA, GA3 in the root, stem, the content of ABA in the leaf and the contents of starch of tuberous root. ABA, GA3 in the stalks mainly facilitate the tuberous root starch accumulation through the influence of photosynthesis product loading and transport. In root formation and expansion period, the content of CYT in root tubers of the high starch cassava varieties 'Fuxuan01' was higher and longer duration that SC124. High significant negative correlation between IAA, CYT, ABA of the leaf and the contents of starch of tuberous root. As the root mature, this three endogenous hormones had the varying degree rise, which may be related to its anti-aging ability.In the Root tuber of maturity, the content of GA3 in stem SC124 was significantly higher than 'Fuxuan 01', the ABA content in root and leaf of 'Fuxuan 01' was significantly higher than SC124 at later growth stage. It showed that low starch cassava varieties was not easy to premature aging, but the excessive growth of the ground part was bad for tuberous root starch accumulation.