Abstract: To improve the effective and comprehensive control technologies of pear leaf diseases and early defoliation in hot and humid producing areas, the differences of ‘Cuiguan’ pear’s leaves and shoots growth, leaf diseases and early defoliation between shallow groove with root protecting and deep groove with root cutting were compared. The result showed that deep groove with root cutting had significantly control effects for pear leaves and shoots growth, leaf diseases and early defoliation, compared with shallow groove with root protecting. After root cutting, single leaf weight and area, new shoot length and internode length decreased 0.15 g, 4.75 cm₂, 18.9 cm and 0.42 cm; SPAD value of chlorophyll content increased 4.43; shoot growth period shortened 16 d; disease indexes of pear spot disease, brown patch, black spot, anthracnose decreased 0.204, 0.026, 0.027 and 0.050; the rates of defoliation in middle of August, September and October reduced 12.9%, 36.7% and 14.5% respectively. In the 2_nd and 3_rd year after treatment, compared to the control, the growth inhibition of shoots decreased obviously; the control of leaf diseases and early defoliation had continuous efficiency; the differences of 4 disease indexes and the rates of defoliation in middle of August, September and October maintained significant and extremely significant different. Deep groove with root cutting could use as matching measures for controlling of pear leaf diseases and early defoliation, which need to implement every 3 years with applying base fertilizer in autumn or winter.