Agricultural land is the basis and guarantee for the survival and development of human. How to take scientific and effective use of agricultural land is an urgent problem to be solved. The suitability assessment can provide a good answer to this question. In order to realize the scientific, reasonable and efficient use of agricultural land under the lack of information condition, we carry out research on the multi-scale suitability assessment of agricultural land. The multi-scale model and index system for land use suitability assessment is put forward based on Geographic Information System, the improved Analytic Hierarchy Process method, and the iteration method considering the actual situation and characteristics of the specific region, Laos Savan District. The results show that the multi-scale assessment can maintain internal consistency in the same assessment unit and keep the heterogeneity between different units from macroscopic scale to microscopic scale. The multi-scale assessment method can make good use of the advantages of controlling land use orientation at macro scale, maintaining data precision at micro scale, and filling the missing data by extracting information from one scale to another. The research model reflects the relationship between each scale. And it can improve and deepen the suitability assessment method according to the actual land use demand. This study is helpful to take a reasonable use of agricultural land. It can provide reference in land use related research and practice in Laos and other countries in the world.