The cylinder head is equipped with intake and exhaust ports, valve seats, valve guides into the hole, also with cooling water channels and lubricating oil channels on the cylinder head of gasoline engines with spark plug holes, diesel engine cylinder head with injection holes.

The cylinder head is part of the gas distribution mechanism of an internal combustion engine, and is mainly used to close off the top of the cylinder to form the combustion chamber, as well as the camshaft and rocker arm shaft, and the intake and exhaust pipes. Burning the fuel in the cylinder generates the kinetic energy to move the piston back and forth in the engine cylinder, which drives the connecting rod connected to the piston and the crank connected to the connecting rod to make a reciprocating circular motion around the center of the crankshaft and power output.