Abstract: 【Purpose/significance】In order to further enhance the use value of students' teaching evaluation information, an index sys⁃tem of online teaching user demand is constructed, and topic mining of online teaching demand data is carried out.【Method/process】Using the data mining theory and LDA topic identification model, the potential online teaching topics are mined from the rich online teaching evaluation content, and the structure mapping is carried out to the user needs according to the characteristics of the teaching topics, and finally the online teaching demand index system is formulated.【Result/conclusion】Based on the analysis of online teach⁃ing data, a user demand index system of online teaching is constructed from three aspects: teacher demand, course demand and teach⁃ing achievement demand, and the optimization strategy of teaching quality is proposed.【Innovation/limitation】Through topic mining of online teaching demand data, this paper provides a new approach and method for the construction and improvement of online teaching evaluation index system of colleges and universities. However, the sample data is only based on a single university, which has not achieved full coverage, and there are still some deficiencies in the overall situation analysis of the research in the field.