With the wide application of spatiotemporal data, more and more data need to be modeled. Fuzziness is one of the important characteristics of spatiotemporal data, but most of the existing spatiotemporal data models are regarded as accurate data and most of the spatiotemporal data models are static. The purpose of this paper is to build a fuzzy spatiotemporal data model based on UML by expanding the standard modeling language UML. On this basis, the historical topological state, effective time, and transaction time are added to make the model dynamic, that is, the states of multiple times are combined together to form a timeline to represent the development process of a fuzzy spatiotemporal entity. Considering the fuzziness of data and the dynamic development of objects, the model can describe the fuzzy spatiotemporal objects better, and make the model dynamic. At the same time, the operation of the UML class diagram is added to make the model data exercisable and compared according to their own needs, which increases the practicability of the model. Finally, an example of land desertification in Alashan is given, to prove the practicability of the model constructed in this paper. INDEX TERMS Dynamic, historical topological state, modeling, spatiotemporal, UML.