The global problem of academic staff retention affects developed countries the same way as it affects developing countries. Perceived organizational support (POS) is a situation where employees develop an attitude or a belief about the degree to which their organization values their contributions and cares about their welfare. The objective of the present study is to examine the effects of perceived organisational support and employee biographical characteristics (age, gender, tenure in the university, tenure as an academic, job position and education) on academic staff retention in universities in Kenya. The sample of the study consisted of 388 academic staff drawn from a population of 13,441 academic staff in 31 public universities and 32 private universities in Kenya. Questionnaire method was used to collect data which was analyzed using inferential statistics which included Independent Samples t-Test, One Way Analysis of Variance (ANOVA), Pearsons Correlation analysis and Multiple Regression analysis. The analyses showed that the mean scores of Perceived Organisational Support (employees welfare) and POS (employees opinion and goals) did not differ significantly on the basis of gender, age, tenure in the university, tenure as an academic and university sector. In addition, the study found that the mean scores of POS (employees' opinions and goals) differed significantly on the basis of job position while mean scores of POS (employees' welfare) differed significantly on the basis of level of education. Further, the results showed that the mean scores of retention differed significantly on the basis of age, tenure in the university, tenure as an academic and job position. The results of correlation analysis showed that Perceived Organisational Support had a significant positive relationship with academic staff retention. Further, the results of multiple regression analysis showed that age and Perceived Organisational Support were significant positive predictors of retention. Finally, the results of multiple regression analysis showed that POS (employees welfare) influenced retention in public universities while POS (employees' opinions and goals) influenced retention in private universities. The study recommended that Universities should improve welfare matters such as pay, incentives, medical insurance among others and that Universities managers should be willing to listen to the employees concerns, soliciting their opinions and giving credit for implemented suggestions. The study further recommended that top university policy makers should implement various retention strategies targeting academics in the positions of senior lecturer and professors, and those with longer tenure in academics and in their universities.