[Purpose/significance] Cross-institutional scientific research cooperation is not only affected by external factors, but also by the internal factors of institutions themselves.This paper aims to reveal the key factors affecting cross-institutional scientific research cooperation from the internal level of institutions themselves, in order to deeply explore the internal formation mechanism of cross-institutional scientific research cooperation, and provide quantita? tive reference for further promoting the orderly, efficient and continuous cooperation among researchers in different in? stitutions. [Method/process] Methods such as decision tree model, k-means clustering, bibliometric, social network analysis are used in the integration.Taking 558 institutions of colleges and universities that have published papers in 14 Chinese journals in the field of computer science and technology included in CSCD from 2019 to 2021 as samples, based on objective empirical data from various sources, this paper explores the influencing factors of cross-institutional scientific research cooperation from the internal level of the institutions themselves, and analyzes the importance differ? ences between different factors. [Result/conclusion] It is found that institutions of colleges and universities with strong comprehensive strength and rich research resources do not necessarily have a higher level and influence of cross-insti? tutional scientific research cooperation, but many institutions of colleges and universities with general comprehensive strength are more likely to have cross-institutional scientific research cooperation.At the same time, among many inter? nal factors of institutions of colleges and universities,strength of major is the most important factor affecting cross-insti? tutional scientific research cooperation.Scientific and technological funding,training level of major,history of major es? tablishment can also have an important impact on cross-institutional scientific research cooperation to a certain extent, respectively.Although the number of scientific and technological projects, the level of school running in colleges and universities, and the accumulation of papers in the early stage can respectively have a certain impact on the cross-insti? tutional scientific research cooperation, their importance is relatively small. In addition, the number of results awards, the number of R&D personnel, and geographical location have a weak correlation with cross-institutional scientific re? search cooperation,which can be almost ignored.