Purpose The purpose of this study is to investigate the factors that influence the adoption of Higher Education Commission (HEC) National Digital Library among research students in different universities of Pakistan. Design/methodology/approach The study framework was based on technology acceptance model (TAM). A sample of Pakistani university students completed the questionnaire measuring the effects of extraneous stimuli through cognitive responses on adoption of the HEC digital library. To test the research hypotheses, multiple regression analysis was used. Findings The findings revealed that: cognitive responses predicted students’ intention of using HEC digital library; extraneous variables significantly influenced cognitive responses; system characteristics directly influenced usefulness and ease of use; interface characteristics directly influenced cognitive responses; and individual differences significantly affected the ease of use. Similarly, system quality was identified with the highest direct effect on usefulness, whereas navigation had the highest influence on easy use of the HEC digital library of Pakistan. In addition, usefulness was explored with the highest effect on intention to use the HEC digital library of Pakistan. The findings revealed that individual behaviours influence the use of digital libraries which imply that acceptance of an information system (IS) involve cognitive idiosyncrasies. Findings of the study are useful for Pakistani academic librarians to enhance adoption and usability of the HEC digital library of Pakistan. The study extended cross-cultural validation of TAM and explored how that Pakistani university students utilize HEC digital library. Research limitations/implications These findings have significant implications for librarians in developing countries, such as to evaluate usability of digital libraries from individuals’ perspective, create awareness, customize users’ interface and train students in navigational techniques. It may also facilitate librarians to improve their current levels of library assistance and emphasize the usefulness of digital libraries towards academic excellence. The findings equally suggest that individual behaviours influence the use of digital libraries because acceptance of an information system involves cognitive idiosyncrasies. This study explored all possible links between the study constructs and emphasized that findings are useful to enhance the adoption and usability of digital library in the developing countries. Originality/value This study is the first attempt that empirically assessed the adoption of digital libraries in terms of Pakistani research students. The study validated TAM in the context of Pakistani university librarianship that extended the cross-cultural validation of TAM. Furthermore, the study focused on real constructs instead of dummy variables and predicted significant effects on acceptance and rejection of digital libraries.