Abstract: 【Objective】The study aimed to provide a scientific guidance for the timing of planting oil tree and a theoretical reference to reducing non-point source pollution in the Three Gorges Reservoir Region.【Method】Vernicia fordii (Hemsl.)Airy Shaw seedlings were grown in pot soil under different concentrations of paraquat(volume ratio of the original medicine and water of 1/50,1/100,1/200,1/400,and 1/800 )and dimerthoate(volume ratio of the original medicine and water of 1/125, 1/250, 1/500, 1/1 000, and 1/2 000), with water as a control(CK), and the soil enzyme activities, efficiency nutrient content, and growth of seedlings were measured after 30 and 60 days, respectively.【Result】 The pH was not significantly difference among pesticides treatments and CK(P>0.05).The soil urease, protease, catalase, and alkaline phosphatase of soil had lower activity than that of CK,30 or 60 days after treatment with high concentrations(paraquat ≥1/200, fenvalerate-dimerthoate≥1/500), and the differences between them were significant in 30 days(P<0.05). However, the urease and alkaline phosphatase of soil had slightly higher activity than that of CK(alkaline phosphatasewas excluded), the protease and catalase of soil had slightly lower activity than CK had, all of them were studied 30 and 60 days after treatment with conventional concentrations(paraquat=1/400,fenvalerate-dimerthoate=1/1 000), but the differences between them were not significant in 30 or 60 days(P>0.05). The nitrogen content was significantly decreased 30 or 60 days after treatment with high concentrations(paraquat ≥ 1/200, fenvalerate-dimerthoate ≥ 1/500), but the nitrogen content was not significantly different between the CK and the pesticide treatment with conventional concentration(paraquat,1/400; fenvalerate-dimerthoate,1/1 000)(P>0.05).Similarly, the available P and available K contents were higher than that in CK,30 and 60 days after treatment with concentrations(paraquat ≥ 1/200,fenvalerate-dimerthoate ≥ 1/500), and they were not significantly different between the CK and pesticide treatments with conventional concentrations(paraquat,1/400; fenvalerate-dimerthoate,1/1 000)(P>0.05).The relative analysis of soil enzyme activities and available nutrients showed that available P and available K were significantly negativly correlated with urease, protease, and catalase. In addition, the growth of plant height, diameter, and biomass of seedlings were decreased under the high concentrations of paraquat(≥1/200)and fenvalerate-dimerthoate(≥1/500)treatment. However, the two pesticides with conventional concentrations(paraquat,1/400; fenvalerate-dimerthoate,1/1 000)had no significant effect on the growth of seedlings(P>0.05).【Conclusion】The results of the present study indicate that highly-concentrated paraquat and fenvalerate-dimerthoate obviously decrease the activity of urease, protease, catalase, and alkaline phosphatase, which reduce the soil nitrogen content and inhibit the activity of available P and K.Thus,the growth of seedlings can be affected because of plants cannot absorb nutrients from the soil. However, paraquat and fenvalerate-dimerthoate do not have any significant effects on soil enzyme activities and effective nutrient contents of Vernicia fordii seedlings under conventional concentrations. Moreover, applying pesticides with conventional concentrations can achieve the effect of weeding and plant disease control. Therefore, reasonable concentration of pesticides should be applied, according to which they can achieve the effect of killing weeding and insects, and will not have a negative effect on soil environment and crop growth.