Abstract: The effects of root cutting on root system distribution and senescence character of peanut （Arachis hypogaea） under different seedling conditions were investigated by using the box culture method. The results showed that, with three types of peanut seedlings, including overgrowing, strong and week seedlings, root cutting all first restricted and then promoted the root system growth, especially promoted the root growth to deep soil. This effect was stronger on the overgrowing and strong seedlings, while relatively weaker on the weak seedlings. After root cutting, root activity, superoxide dismutase (SOD) and peroxidase (POD) activity all reduced at first, and then increased, compared with each control. The extents of decrease in root activity, SOD and POD activity were highest in the weak seedlings, lowest in the overgrowing seedlings, and moderate in the strong seedlings. However, in the later stage after root cutting, the extents of increase in root activity, SOD and POD activity were higher in the overgrowing and strong seedlings, than in the weak seedlings. Generally, root cutting could promote the root activity of peanut and delay the senescence.