The spatial variability of soil erodibility (K-factor) in small watershed scale and the correlation between K-factor and land use, vegetation type, soil physical and chemical properties were the scientific basis of quantitative soil erosion research and small watershed comprehensive management. Based on testing to physical and chemical properties of 66 soil samples, in which K value was calculated by EPIC model and the spatial map of K-factor was obtained by geostatistical and kriging spatial interpolating methods, the spatial variability of soil erodibility (K-factor) and the influence of land use and vegetation cover to K value in the watershed of Jianshan river in the catchment of Fuxian lake in Yunnan province were studied in this paper. The results showed that: (1) The distribution of K value in the studied area was even, with the range of K value from 0.1628 to 0.3836, the mean of 0.2824, and the median of 0.2885, the mean was very close to the median, and the spatial variability of K value was moderate difference, with the variance coefficient of 17.98%; (2) The K value of different soil texture was different at a certain degree, and the order from big to small of K value of main soil texture in the studied area was respectively silty loam, loam, clay loam, and sandy loam. (3) The main soil erodibility levels in the studied area were middle (with K value between 0.25~0.30), higher-middle (0.30~0.35) and lower-middle (0.20~0.25), their area were respectively 1797.88 hm2, 1185.51 hm2 and 542.32 hm2, which were account for 50.76%, 33.47% and 15.31% of the total area of the studied small watershed, and the areas of high erodibility (>0.35) soil and relatively low erodibility (0.15~0.20) soil were very small, and there had not low erodibility (<0.15) soil; And in the respect of spatial distribution, soil erodibility level was lower-middle in northern high mountain area of the small watershed, higher-middle in the lower elevation area of southern and central area, middle in the other area of southern and central area, and the spatial distribution of K value in the studied area had strong correlation with altitude. (4) The influence of land use and vegetation coverage to K value was obvious, and the order from small to big of K value of main land use and vegetation coverage in the studied area was respectively forest land, scrub-grassland, grassland, nonirrigated terrace land, garden, nonirrigated slope farmland and paddy field, the K values of vegetation types such as forest land, grassland and scrub-grassland, which had a few human disturbance or without human disturbance, were smaller, while the K values of land use types such as garden, nonirrigated slope farmland, nonirrigated terrace land and paddy field, which had more human disturbance, were bigger, that is to say, the K value had strong correlation with land use, vegetation coverage, agricultural activity frequency and disturbance degree such as scarification, weeding and farming.%小流域尺度的土壤可蚀性 K 值空间分异特征及其与土地利用、植被类型、土壤理化性质等相关关系的研究，可以为小流域土壤侵蚀定量研究及综合治理决策提供科学依据。以云南省抚仙湖库区尖山河小流域为研究区，在大密度土壤采样和土壤理化性质测试分析的基础上，采用EPIC模型K值计算方法、地统计学方法和Kriging空间插值方法，计算分析了尖山河小流域土壤可蚀性K值的空间变异特征及土地利用/植被覆盖对K值的影响作用。结果表明，（1）研究区K值变化范围为0.1628~0.3836，均值为0.2824，中值为0.2885，均值与中值相近似，表明K值分布较均匀；变异系数为17.98%， K值存在中等程度的空间变异性。（2）不同土壤质地类型的K值存在一定差异，研究区主要土壤质地类型K值从大到小依次为粉壤>壤土>粘壤>砂壤。（3）研究区以中可侵蚀性（0.25~0.30）、中高可侵蚀性（0.30~0.35）和中低可侵蚀性（0.20~0.25）土壤为主，面积分别为1797.88 hm2、1185.51 hm2和542.32 hm2，分别占小流域总面积的50.76%、33.47%和15.31%，而高可侵蚀性（>0.35）土壤和较低可侵蚀性（0.15~0.20）土壤分布面积较少，无低可侵蚀性（<0.15）土壤；在空间分布上，北部高山区土壤具有中低可侵蚀性，中、南部的低海拔区土壤具有中高可侵蚀性，中、南部其余区域土壤具有中可侵蚀性，这种空间分布与海拔存在较强的相关关系。（4）土地利用/植被覆盖对K值具有明显的影响作用，研究区主要土地利用/植被覆盖类型 K 值从小到大依次为林地<灌草地<荒草地<旱平地<园地<旱坡地<水田，需频繁松土、除草、耕作和扰动的土地利用/植被覆盖类型（园地、旱坡地、旱平地和水田）其K值较大，而无需耕作、扰动小的土地利用/植被覆盖类型（林地、荒草地和灌草地）其K值较小，这表明K值的大小与土地利用/植被覆盖类型及松土、除草、耕作等农业生产活动频次和扰动程度存在明显相关性。
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