The level of revenue generated in the state has been in a declining form due to poor administration and collections of taxes and lack of proper return of accounts. These are the negative effects that affect government revenue generation which are targeted to meet her basic functions like provision of basic amenities for her citizenry in the state. The aim of this research study is to evaluate the effect of tax administration on revenue generation to the Enugu state government. The research design adopted in this study was survey research method. Primary and secondary sources of data were used in collecting information which was analyzed using simple percentages and hypothesis tested using chi –square statistical method at 0.05 level of significant for validity and to make decisions. Findings show that there was rampant incidence of tax evasion and avoidance in the state, and the tax administration in Enugu state is inadequate, not effective and not efficiently managed thus: inadequate staff and facilities also hinder tax administration and collection. The researcher, in the final analysis drew a lasting conclusion, some of which are:- the apathy of Enugu state people towards payment of tax could be reduced by involving them in the decision making of tax administration, collection and utilization of the tax revenue. The environment should be made better by both the government and its agencies. The staff of the SBIR Enugu should be well remunerated and ensure adequate administration of tax laws in accordance with the laid down rules and regulations.