This paper depicts about electronic fuel injection system for two-wheeler applications which have emerged in recent years and are commercially available. Electronic fuel injection system utilizes both electronic and electrical devices to observe and control engine process. An EFI system is a replacement for carburetor which mixes the air-fuel. EFI injects the fuel directly into an engine’s manifold or in a cylinder with the electronic controls. The types of EFI are: Throttle body injection system in which an injector (throttle-body injector) delivers fuel into the center point inside an intake manifold of the engine, Multipoint injection (also known as PFI (port fuel injection)), injects the fuel into the entry ports at upstream of every chamber’s entry valve, instead of a main issue inside an admission. Direct fuel injection system in which it delivers fuel directly into a single combustion chamber formed in the cylinder space. An electronic fuel injection system provides an opportunity to mix the air-fuel ratio for every cylinder in an accurate manner and simultaneously by controlling the air mass flow rate, by injecting the suitable fuel mixtures, fuel delivery is being controlled from each cylinder. Furthermore, the ignition and injection timings are optimized as well.