Taking a leap from the perspective of organizational citizenship behaviour, pro-social behaviour examines how volunteering intentions such as helping or assisting colleagues, to how collaboration tendencies such as selfless or willful participation in workplace functions, events and issues can affect or influence administrative sustainability and longevity. This study examines the impact of pro-social behaviours on workplace performance and sustainability of university administration. Adopting the survey research design, respondents comprised both the academic and non-academic staff of the University of Nigeria, Enugu campus. The data collected were analyzed using the simple linear regression tools of the Statistical Package for Social Sciences, Version 20. Findings revealed that volunteering impacts the longevity development of university administration, while collaboration affects the competitive edge of university administration. The study thus concluded that pro-social behaviours influence the performance and sustainability of university administration.