Differentiated Instruction (DI) is a hot topic in educational research. Keeping abreast of its latest developments and frontiers can provide new perspectives for future study. Using CiteSpace software, 1086 publications included in the Web of Science core collection from 2000 to 2020 were analysed to create knowledge maps of DI research. The findings show that, firstly, the number of DI-related publications is fluctuating upwards. Secondly, The United States is a world leader in DI research. Thirdly, the core group of authors has not yet formed. Fourthly, the main research hotspots are Universal Design for Learning, Behaviour, Assessment, Text Features, Science Education and Concept Inventory. Fifthly, the development of DI research can be divided into three phases: 2000-2007, 2008-2014, and 2015-2020. On this basis, the future direction of DI research is discussed and suggestions are given accordingly.