Abstract: The dynamic features of biochemistry contents in the leafblades of Sargentodoxa cuneata under natural conditions were studied. The results showed as follows. The dynamic changes of the content of soluble sugar, starch and total sugar were similar. The content of them was low in the forepart of growth season, and ascended gradually with the growth of leafblades. The maximal content reached at August, then declined gradually. There were distinctly positive correlation between the content of total sugar and the average diurnal net photosynthetic rate. In the whole growth season, the content of soluble sugar was higher than that of starch. The seasonal change of total protein in the leafblades of Sargentodoxa cuneata showed as unimodal curve. The content of protein was low at the early stage of the spread of leafblades, and then it ascended quickly. The maximal content reached at June, then it declined gradually and the minimal content reached before defoliation. The seasonal change of soluble protein was similar to that of total protein. The content of DNAascended at a large extent at the early stage of the growth of leafblades. The peak reached at June and declined rapidly, then it inclined to stabilization on the whole. The content of RNA ascended in a sort with peak at June, then it declined slowly while the minimal content reached at September and the content went back a little before defoliation. The seasonal content change of nucleic acid was similar to that of RNA. The ratio of RNAto DNA reached 3 pinnacles in the whole growth season. In a whole growth season, the dynamic patterns of flavonoids in the leafblades of Sargentodoxa cuneata were bimodal curve. The first peak was reached at May while the second peak was reached at September.