It is known that internal combustion engines, both spark and compression ignition can be modified from single fuel to bi-fuel system engine. As example methane or hydrogen gas can be used as auxiliary fuel to run spark or combustion ignition engine. In case of that modification many engine fuel supply parts should be modified, or engine should be supplemented with additional equipment to fully control the mixing and combustion of bi-fuel. In case that physical and chemical properties of hydrogen is different from gasoline fuel, main attention should be paid for safety and control of gas caused by high risk of gas explosion. This study is focused on evaluation of hydrogen supply equipment requirements, types, and compatibility with internal combustion engine, also on how hydrogen performance is depended on gasoline engine supply parts. © 2023 Kaunas University of Technology. All rights reserved.