A liquid ejection head has an ejection port forming region which includes liquid ejection energy generating elements arranged on a substrate, liquid supply ports each running through the substrate and having an opening at a surface of the substrate, a liquid path formed on the surface as a space containing the liquid ejection energy generating elements and the liquid supply ports therein, and ejection ports corresponding to the respective liquid ejection energy generating elements. The liquid ejection head is manufactured by forming a liquid path forming layer on the substrate using a dry film resist, forming an ejection port forming layer on the liquid path forming layer, forming a liquid path in the liquid path forming layer and ejection ports in the ejection port forming layer. The substrate has dummy holes each having an opening at a surface of the substrate outside the ejection port forming region.