A cooling unit includes: a heat-radiating section in which a coolant flows and which radiates heat caught by the coolant; and a path where the coolant flows through the heat-radiating section; a pump on the path to cause the coolant to flow; and heat absorbing sections disposed on the path to touch heat-producing elements having different heating values, in which the coolant runs to absorb heat produced by the heat-producing elements. One of the heat-absorbing sections is a maximum-heat-absorbing section that touches a maximum-heat-producing element and is disposed downstream from the pump and upstream from the heat-radiating section in a flow of the coolant on the path. Another one of the heat absorbing sections is a low-heat absorbing section that touches the heat-producing element except the maximum-heat-producing element and is disposed upstream from the pump and downstream from the heat-radiating section in the flow of the coolant on the path.