A liquid ejection head including an ejection device substrate having a substrate provided with an energy-generating element that generates energy for ejecting a liquid, a liquid supply member that supplies the liquid to the ejection device substrate, and a support member that is provided between and joined to the ejection device substrate and the liquid supply member. The support member has at least two liquid supply flow paths that are through-holes extending through the support member and has a projected or depressed portion at its joint surface with respect to the liquid supply member. A spacing between two adjoining liquid supply flow paths at the joint surface with respect to the liquid supply member is larger than a spacing between the adjoining two liquid supply flow paths at a joint surface of the support member with respect to the ejection device substrate.