The experiments were carried out to test the effects of forest thinning on soil labile organic carbon in a Pine-oak mixed forest in the Qinling Mountains. The quadratic general rotary design was applied, and thinning intensity and residue removed intensity were considered as factors in the experiments. Based on field sampling and laboratory analyzing, the characteristics of soil labile organic carbon under different thinning and residue removed intensities were analyzed. The contents of DOC (dissolved organic carbon) and MBC (Microorganism biomass carbon) ranged from 42.65 mg·kg-1 to 86.03 mg·kg-1, and from 91.30 mg·kg-1 to 510.76 mg·kg-1 respectively. The ratio DOC/TOC (total organic carbon) and MBC/TOC ranged from 0.20% to 0.39%, and from 0.41% to 2.05%respectively. When they were maximized as 84.95 mg·kg-1 (DOC), 390.76mg·kg-1 (MBC) in the depth of 0~10 cm in soil and 59.65 mg·kg-1 (DOC), 293.60 mg·kg-1 (MBC) in the depth of 10 to 20 cm soil, the thinning intensity and the residue removed intensity were 16.34% ~ 17.05%and 35.86% ~ 40.69%. The thinning intensity was the key factor to affect MBC and DOC (in the depth of 0 ~ 10 cm soil). In the depth of 10 to 20 cm soil, the residue removed intensity changed as the key factor to affect DOC. Providing the availability of soil organic carbon would achieved most fully, the thinning intensity and the residue removed intensity were 16.34%~17.05%and 35.86%~40.69%.%为探讨抚育间伐对林地土壤活性有机碳的影响，以秦岭火地塘林区松栎混交林为研究对象，通过野外采样和室内分析，对不同间伐强度和间伐残留物移除强度下土壤活性有机碳特征进行了研究。结果表明：不同间伐强度和间伐残留物移除强度下，土壤水溶性有机碳(DOC)和微生物量碳（MBC）含量分别在42.65～86.03 mg·kg-1和91.30～510.76 mg·kg-1之间波动，占土壤总有机碳（TOC）的比例范围分别为0.20%～0.39%和0.41%～2.05%；当间伐强度为16.34%～17.05%、间伐残留物移除强为35.86%～40.69%时，土壤DOC和MBC含量在0～10 cm和10～20 cm土层分别可达到最大值84.95、59.65 mg·kg-1和390.76、293.60 mg·kg-1；间伐强度是影响土壤MBC含量和0～10 cm土层土壤DOC含量的主导因子，间伐残留物移除强度是影响10～20 cm土层土壤DOC含量的主导因子；土壤中有机质含量的有效性达到最佳，间伐强度和间伐残留物移除强度的最适设置范围分别为16.34%～17.05%和35.86%～40.69%。
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