Today in many organizations in the public sector, the use of IT has become crucial in sustaining and extending the organizations’ strategies and objectives. Such use of technology has caused a critical dependency on IT thus a call for specific focus on IT governance. Despite increased practice of IT governance in these organizations, little academic empirical research has been undertaken to investigate its maturity, which is even worse in a developing country environment. Therefore this paper, based on the 15 most important processes of the COBIT framework and a case study in five public sector organizations, establishes IT governance maturity in the public sector in a developing country like Tanzania. In addition, the study result is compared against a similar benchmark in the public sector in a developed country like Australia and internationally from a range of nations. The result indicates some IT processes to have scored relatively lower maturity but very important to the process of IT decision making and monitoring in the studied environment. In addition, it indicates the maturity to be relatively lower in the organizations with less established IT governance mechanisms. Moreover when compared with the public sector organizations from Australia as a developed country and internationally from a range of nations, the IT governance maturity pattern turned out to be relatively lower in all studied IT processes. Finally, based on these results, recommendations are provided to improve poorly performing processes for successful IT governance in support of better public service delivery in this environment.