This study examined the challenges associated with knowledge management implementation and academic staff retention in selected tertiary institutions in South East, Nigeria. The research design adopted was a cross-sectional survey design. The main instrument used for data collection was questionnaire. The population consisted of 7,423 academic staff of the 10 randomly selected institutions in the South East Nigeria. A total sample size of 555 was drawn from the population. The instrument was checked for reliability using Cronbach method and the reliability co-efficient result of 0.915 showed that the instrument had high degree of item reliability. The hypothesis formulated was tested using Friedman chi-square statistics. The findings indicate that there is positive significant challenge in knowledge management implementation and academic staff retention in selected tertiary institution. The study concluded that lack of Knowledge Management implementation has posed a great challenge in academic staff retention in tertiary institutions. It was advised that tertiary institutions in Nigeria should adequately manage the process of knowledge acquisition, sharing and development so as to enjoy a Stella performance.