The aim of the present paper is to investigate the effects of root cutting on leaf photosynthetic characteristics and yield of peanut, which can provide the theoretical basis for root cutting applied to peanut production as an agronomic technology. Under the field condtions with Arachis hypogaea L. cv. ‘Qinghua 5’ as the experimental materials in 2011 and 2012, the experiments was conducted to study the effects of root cutting at different growth stages on functional leaf photosynthetic characteristics and yield of peanut. The experiments were subjected to five treatments at different growth stage: root cutting on the fifth day after the first flowering date(T1), the tenth day after the first flowering date(T2), the fiftieth day after the first flowering date(T3), the twentieth day after the first flowering date(T4), and the twenty-fifth day after the first flowering date(T5), while the intact plants without root cutting were taken as the control treament(CK). The results showed that root cutting (T4) at the suitable stage promoted the leaf growth, significantly improved the leaf area index (LAI) and functional leaf chlorophyll content, moreover, maintained a longer time of higher LAI and chlorophyll content until later growth stage, compared with CK and other treatments, .Root cutting (T1, T2) at the early stages caused low growth speed and LAI peak value. LAI decreased rapidly at the late growth stage. The chlorophyll content in the functional leaf of T1 and T2 treatment was higher than that of CK, but significantly lower than that of T4 treament. Root cutting (T5) at the later stage was unfavorable to the development of LAI and maintaining high chlorophyll content. under By root cutting at the optimum stage, the net photosynthetic rate, stomatal conductance, and transpiration rate of functional leaves were higher, and the intercellular CO₂ was lower compared to the other treatments, which significantly improved the photosynthetic efficiency of functional leaves. Under root cutting too early, there were low peak values of the net photosynthetic rate, stomatal conductance, and transpiration rate of functional leaves. At the same time, these photosynthetic characteristics of functional leaves dropped fast after the peak value, and decreasd to lower level at the late stage, except the intercellular CO₂ maintaining at a high level all the time. Root cutting too late did not affect the leaf photosynthetic characteristics of peanut. Root cutting at the optimum stage increased pod number and weight per plant, and improved the productivity per plant, with the high pod yield and economic coefficient of peanut. The pod yield under the T4 treatment reached 4148 kg/hm², which improved by 9.1% compared to CK. Pod number and weight per plant improved by 7.1% and 3.3% compared to CK, respectively. Root cutting at the early stages reduced the yield, moreover, the earlier root was cut the lower yield peanut reduced. Pod yield of peanut under T1 treatment reduced by 10.3%. Root cutting too late has the less influence on pod yield of peanut. It was concluded that root cutting on the twentieth day after the first flowering date can be used as a management practice of peanut cultivation.