As the core of the new generation of test theory,cognitive diagnosis is a new diagnostic technique based on the development of modern cognitive psychology and psychometrics,modern statistical mathematics and computer science. It has been applied in the field of English education,for the English reading test based on cognitive diagnosis evaluation can measure students' knowledge structure,processing skills or cognitive process,its results can provide cognitive diagnostic feedback. At present,the cognitive diagnostic evaluation of English reading has become a research focus of foreign scholars and has also attracted wide attention from Chinese scholars. This paper reviews cognitive diagnosis from five aspects: its development,theoretical basis,its application in English reading and the difficulties and shortcomings of existing research,as well as its summary and prospect in order to promote the application of cognitive diagnosis in English education,especially in English reading tests in China.