A liquid ejection head includes, a first support member including a flow path for supplying liquid and an opening communicating with the flow path; at least one second support member that includes an individual liquid chamber communicating with the opening and arranged on the first support member along the flow path; and a recording element substrate including an energy-generating element for generating energy for ejecting the liquid, and a supply port for supplying the liquid to the energy-generating element, the supply port communicating with the individual liquid chamber, the recording element substrate being supported by a back surface of the second support member with respect to an opposite surface thereof facing the first support member. When P (μJ/pL) represents energy to be input per ejection liquid droplet volume in the energy-generating element, thermal resistance R (K/W) of a shortest heat transfer path of the second support member between the recording element substrate and the first support member satisfies: R≧1.4/ln{0.525e1.004P−0.372}−1.