Exhaust manifold-integrated cylinder head with water jacket

An exhaust manifold-integrated cylinder head with a water jacket includes intake ports through which outside air is supplied and exhaust ports through which exhaust gas is discharged from a combustion chamber. Intake valve holes and exhaust valve holes open the intake ports and the exhaust ports. Spark plug holes are formed on a top side of the cylinder head. A head water jacket is formed within the cylinder head to allow a coolant to flow from one end to another end. The head water jacket includes exhaust port bridge coolant passages formed between the exhaust ports. Lower coolant guides protrude inside the cylinder head so that the coolant flows upward from a bottom side of the cylinder head through the exhaust port bridge coolant passages.