This disclosure deals with a variable fluid pressure regulator wherein the level at which the fluid pressure is regulated is adjustable. A member has a flow passage formed therein, and the fluid flows through the passage and out of the member, and a closure is positioned over the opening. The closure is yieldably mounted relative to the member and a spring urges the closure toward the opening. A recess or cavity is formed in the closure, and the fluid flows from the opening, into the recess, and then through a space between the closure and the member. The fluid pressure in the passage is a function of the spring force and the effective area of fluid pressure on the closure, and the effective area comprises the area of the opening plus any area of the recess which lies outside the margin of the opening. The regulated fluid pressure level may be varied by laterally shifting the closure relative to the opening in order to change the effective area.