This study analyzes the difference of Operation & Maintenance (O&M) costs between government's budgeting method and an alternative approach using Analytical Hierarchy Process (AHP). The AHP was used to determine the formula of budget distribution by considering irrigation infrastructure, location of irrigation area. The formulation was calculated based on the observation to samples in West Java, Central Java and East Java, three provinces that have significant agricultural contributions in Indonesia. Irrigation areas characteristics assessed were areas, channels, weirs and hydraulic structures. The result shows that the equation had an exceptional different linier relationship compared with the quadratic relation equation. They were far more reasonable having a linier proportionality between the budget and the amount of infrastructure. The conclusion also integrates with the linier relationship. Thus, while the precise equation are not intended to be universal applicable, the most important finding was how O & M budget was correlated positively to the amount of infrastructure, not only depending on the area of irrigation.