<p>A manufacturing method of a liquid ejection head includes a step of performing a first exposure to form a first ejection orifice row and a step of performing a second exposure to form a second ejection orifice row in which ejection orifices are arranged in a row with ejection orifices that form the first ejection orifice row through a connection portion. In an ejection orifice row formed by the first and the second ejection orifice rows, regarding the distances between the centers of ejection orifices in an arrangement direction of the ejection orifices on opening surfaces of the ejection orifices, the ejection orifices are formed so that a distance between the centers of two ejection orifices adjacent to each other with the connection portion in between is longer than a distance between the centers of two ejection orifices adjacent to each other without the connection portion in between.</p>