The eco-hydrological characteristics of natural secondary evergreen broadleaved forest in Miaoshanwu Nature Reserve were studied based on field observations within a time period of one year.The results show that soil moisture of natural secondary forest has significant temporal and spatial variations.The average annual soil moisture content ranged from 14.24%to 22.55%.Similar to precipitation,soil moisture content increased firstly and then decreased during ayear.Soil moisture of the surface layer(0-5cm)exhibited strong variability.With the increase of soil depth,the coefficient of variation of soil water content decreased.Strong variations of monthly slope surface runoff were observed and were found closely correlated with single-event rainfall.In the watershed scale,monthly surface runoff varied in a wide range with a maximum runoff of 389.11mm in August.The results of water quality sampling show that most water quality indices qualified the first level in the governmental standards,except for total N contents and pH values.