The back pressure adjustment apparatus for a liquid ejection head has: a container having a liquid accommodating chamber which is connected to the liquid ejection head and accommodates liquid to be supplied to the liquid ejection head, and a gas accommodating chamber which accommodates gas; a movable film which separates the liquid accommodating chamber and the gas accommodating chamber, and forms a portion of whole walls of the liquid accommodating chamber; and a pressure adjustment device which causes all or a portion of the movable film to deform so as to adjust pressure of the liquid accommodated in the liquid accommodating chamber.