Different of genetypical soybean seedlings were retreated with different concentration of PEG-6000. The result showed that the germination rate and vigour index of soybean seeds pretreated increased notably, the pretreatment with 20% PEG(W/W) for 8hours was the most effective. During germinating period, and the conductivity rate decreased compared to control.The specific activity of superoxide dismutase(SOD)first fast increased, after fast decreased ,while the accumulation of MDA was lower than those of the control.This indicated that the increasing of vigour index and favoring of membrane system’s repair through with feasible concentration PEG.