This study investigated research skills, ICT application and sustainable library development. Descriptive survey research design was used for the study. The population of the study was 142 librarians working in the university libraries of twelve universities in South-west, Nigeria. Purposive sampling technique and total enumeration sampling technique were employed for the study. Data were collected using well-structured questionnaire. Six research questions were raised and three hypotheses were tested at 0.05 level of significance using Pearson-Product Moment Correlation Coefficient. The findings of the study revealed that: sustainable library development was primary to librarians; librarians exhibited high need for research skills that would enable them to perform optimally on their job; development of research skills had enormous consequences on research performance of librarians; and ICT was a necessity in ensuring sustainable library development. Hypotheses tested revealed that there was significant relationship between research skill and sustainable library development; between ICT application and sustainable library development; and the joint influence of research skills and ICT application was not significant on sustainable library development. It was recommended that librarians should maintain high level of research skills and ICT application towards ensuring sustainable library development.