The agricultural land suitability assessment based on the natural characteristics of land blocks is tra-ditionally the basis for agricultural and/or land use plan-ning.The assessment,however,is static and cannot be incorporated with potential land use changes.Recently,a dynamic approach,i.e.,matter element analysis,has been effectively applied for land use planning.In the pre-sent study,based on matter element analysis,we estab-lished a matter element analysis model for land use suitability assessment using the suitability grade of land use,evaluation indicators and their characteristic values as matter elements,and also using sutra field,controlled field,weight value and correlation degree from field sur-vey,as well as an expert system.This model was applied to the structure regulation of the land use in the small Yuejiagou watershed of the Langzhong Municipality in Sichuan Province,China.Results show that the propor-tion among agriculture,forestry and animal husbandry tended to rationalize land use.The economic and eco-logical indices of the lands were increased from 1529.8 to 1719.99 and from 1460.94 to 1758.21 after the regu-lation,respectively.The regulation also caused changes in landscape pattes as follows:The indices of diversity and evenness were increased from 1.3028 to 2.0920 and from 0.6108 to 0.8463,or by 60.58% and 38.56%,respect-ively.However,the indices of dominance and contagion were decreased from 0.6431 to 0.2106 and from 0.7467 to 0.7125,respectively.This indicated that the land use in the small watershed was rational.The spatial distribution of patches tended to be uniform.The patch congregation was gradually dispersed.This study verified that the mat-ter element analysis approach can not only overcome the factitious influences and improve the precision of land assessment,but also can be used for the structure regu-lation of specific patches.