A water-jacket structure of a cylinder head may include a plurality of intake side inlet passages installed at intake sides of the cylinder head, respectively, along a length direction of the cylinder head to introduce cooling water supplied from the water-jacket of a cylinder block into the water-jacket of the cylinder head, a combustion chamber cooling passage cooling a combustion chamber using the cooling water supplied from the intake side inlet passage, a plurality of exhaust side outlet passage disposed at exhaust sides of the cylinder head, respectively, along a the length direction of the cylinder head to discharge the cooling water passing through the combustion chamber cooling passage, and an exhaust side gallery communicating with the exhaust side outlet passage to gather the cooling water discharged from the exhaust side outlet passage.