Abstract: This research applied colorimetric method to explore the interactions of the total soluble sugar content，sucrose content，starch content and the relevant enzyme activity of Chinese‘3113’chestnut in the fruit establishment stage. The starch accumulation sucrose metabolism and relevant enzymes activities were investigated in fruit establishment stage of Chinese chestnut. The results indicated that the transverse and longitudinal diameters show double“S”type，the average weight of Chinese chestnut showed“S”curve. The total soluble sugar content showed an increasing tendency，sucrose content had decreasing tendency，starch content presented as single peak curve. SS and SPS activities which reached the peak point 60 days after flowering，decreased afterward，showed the identical tendency as sucrose variation. All the activity variation of the AGPP，SSS and GBSS presented as single peak curve，but the time were not the same. According to the correlation analysis，soluble starch content which positive correlated to total sugar content significantly，the correlation coefficient was 0.978. The activity of SS and SPS positive correlated to sucrose content significantly，the correlation coefficients were 0.905 and 0.892，respectively. The content of soluble starch positive correlated to SSS and significantly positive correlated to GBSS，the corresponding coefficients were 0.764 and 0.883，separately.

Key words: Chinese chestnut, sucrose, starch, enzyme activities