Abstract: Based on the information theory and fuzzy set theory, in the light of the characteristics of randomicity and fuzziness of part spatial data in GIS,this paper proposes a hybrid entropy model of spatial data uncertainty,and hybrid entropy can be used to measure the total uncertainty of spatial data caused by stochastic uncertainty and fuzziness uncertainty.Taking the uncertainty of line segment as an example,this paper discusses the evaluating methods of statistic entropy,fuzziness entropy,and hybrid entropy of line segment uncertainty.And the entropy-band distribution of line segment uncertainty is shown.