This research aims to identify the concept of customs revenues and their impact on the state’s general budget deficit. The problem of the study stems from the following question: What is the impact of customs revenues on the general budget deficit in Iraq? To answer this question, this research uses the deductive approach and the estimation approach by analyzing and measuring the impact of customs revenues in supporting the state’s general budget. Among the most important results of the study are: There are many reasons that led to the emergence of a deficit in the state’s general budget throughout the study period, the most important of which is the decrease in Customs revenues as a result of the weak role of tax revenues It recommended the need to address the imbalance in the structure of public revenues by activating the role of taxes and fees and reducing dependence on the oil resource.