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Understanding the impact of slope positions on stand transpiration of a plantation is necessary for assessing the hydrological effect of the plantation and furtherly, quantifying the watershed water budget. In this study, we analyzed the variations in hourly, daily, and monthly stand transpiration of a 25 y old Zenia insignis plantation at different slope positions, and its response to climate factors, soil water content, and leaf area index in a karst catchment of north Guangdong province, south China. Results showed that all plots for different slope positions exhibit the same sequence sorted by hourly, daily, and monthly stand sap flux density (Js), which is upper-slope, foot-slope, and mid-slope in descending order. Meanwhile, all plots for different slope positions exhibit the same sequence sorted by hourly, daily, and monthly stand-scale transpiration (E), which is footslope, upper-slope, and mid-slope in descending order. Hourly Js values are positively correlated with solar radiation (Rs), air temperature (Ta), vapor pressure deficit (VPD) (p < 0.001), and negatively correlated with relative humidity (RH) (p < 0.001). Daily Js values are positively correlated with Rs, values are positively correlated with Rs, Monthly Js is mainly affected by LAI. Generally, there is no significant correlation between Js and soil moisture at all hourly, daily, and monthly scale, but there is a strong positive relation between hourly Js and soil moisture in moist days. The findings of this study will assist in evaluating local water budgets in Z. insignis dominated karst catchments of South China. [ABSTRACT FROM AUTHOR]