The study was on the Impact of Financial Control Mechanisms on Local Government Autonomy in Delta State, Nigeria, 1999-2008. The general objective of the study was to establish the nature of relationship between financial control mechanisms and autonomy with a view to exposing the contradictions between policy objectives of government and the actual realisation of the objectives of local government in Delta State. The specific objectives of the study were to: identify the existing financial control mechanisms put in place by both Federal and State Governments and the effects of these mechanisms on autonomy; examine how the whittling down of autonomy of local governments as a result of financial control mechanisms affect service delivery; and recommend measures to ameliorate the negative effects of financial control mechanisms on efficient service delivery in Delta State Local Governments. The data for this study were gathered through questionnaires, interviews, books, journals, government publications, and internet materials. Tables and frequency distribution were used for data presentation. Simple percentages and content analysis techniques were adopted for data analysis. From the findings, 234 respondents, representing 71% agreed that the constitutional powers granted state governments to make laws for the establishment of the structure, composition, finance and functions of local government has whittled down the autonomy of local government while 206 respondents, representing 62% felt that Joint Allocation Committee (JAC) had more devastating effect on local government financial autonomy. The study identified external financial control mechanisms to have had a more negative impact on autonomy than internal financial control mechanisms. Beside the diversion of Federal Allocation to local government by the state government, the burden of the payment of primary school teachers salaries by the councils have reduced the available funds to Delta State Local Governments, making it depend heavily on the higher tiers of government. Poor internal revenue generation mechanisms, corruption, non compliance with existing Financial Memoranda (FM), and other financial regulations by council officials have also affected service delivery. In the light of the above findings, the researcher made some recommendations including but not limited to the following:- that the establishment of the structure, composition, financial and functions of local government should rest in the constitution of the Federal Republic of Nigeria not the state government. The revenue allocation formular should be reviewed from 20.6% to 30% in favour of local government, the federal allocation should be paid directly into local government account instead of the current joint state/local government account; and the burden of the payment of primary school teachers salaries should be taken over by the higher tiers of government to enable local governments have more revenue for capital development.