The fossil fuels and the natural gas reserves that have undertaken the role of the locomotive of the industrial period are limited. It is also the biggest factor in environmental problems. All these reasons lead to the need for alternative fuels or resources. Hydrogen is the candidate to be one of these alternatives; is an unlimited clean and efficient fuel. Hydrogen may assume the role of carrier in the process of storage of other alternative energy sources. Today, interest in hydrogen energy is increasing. One of the reasons for this is that hydrogen can be produced from renewable energy sources such as water, biomass, wind and sun as well as hydrogen from primary energy sources. There is no polluting gas emissions when hydrogen is used as fuel. The HHO dry cell is a device that converts water into HHO (oxyhydrogen) gas. In this study, performance of HHO dry cell with 12×12 plate combination was experimentally investigated and modeled with a Rule-Based Mamdani-Type Fuzzy (RBMTF) modeling technique. Input parameters are; plate number, time, current; output parameter is mass flow rate. The coefficient of multiple determination (R2=98.5) for the mass flow rate. RBMTF results indicated that RBMTF can be successfully used in HHO dry cell with 12×12 plate combination.