Liquid ejection head

A liquid ejection head including a recording element substrate configured with ejection port surfaces each having a liquid ejection port, the liquid ejection head comprising:

• a first positioning member configured with a first positioning part including a recess portion opening in a direction of liquid ejection;
• and
• a second positioning member configured with a second positioning part, which includes a groove portion opening in the direction of liquid ejection and extending towards the first positioning member, and a third positioning part, which has a flat plane substantially parallel to the ejection port surfaces,
• wherein the recess portion of the first positioning part is disposed on a straight line extending from the groove portion of the second positioning part,
• wherein the second positioning part has a first surface which is one of the sides of the groove portion located closer to the flat plane,
• wherein the third positioning part has a second surface connected to the flat plane, and
• wherein the first surface and the second surface are connected on the second positioning member and intersect on an extension line extended in a direction away from the flat plane.