Abstract:In the storage of pollinated cucumber fruits which were harvested in commercial size, the adaxial and middle parts of fruit become withering, while abaxial part become expanding. The contents of protein, DNA, RNA as well as dry weights in the abaxial placenta of fruit increase with storage time going on, while those in middle part decrease dramatically. Simultaneously, seeds in abaxial part develope rapidly. DNase activities in middle pericarp and placenta increase by 5 and 7 times respectively, RNase activities there go up by 5 and 6 times. The two enzymes change little in abaxial part. Different treatments of fruits with plant growth regulators BA, GA3 and NAA show that BA+GA3(20ppm+100ppm) can most obviously delay the speeds of the withering of the middle part and the expanding of abaxial part and the decrease of chlorophyll content. These results may have commercial value in the freshness-retainning and senescence prevention of the cucumber fruits. The non.pollinated fruits have no “abaxial expending”phenomenon during post-harvested storage. The contents of protein etc. decrease almost equally in any part of the fruit.