A foam spray head assembly comprising: a press head connected with a cap; a netted tube having a first net, a second net and a hollow tube; a valve member having a first end and a second end, the first end of the valve member having a first recess, a second recess, an inlet valve and a release path, the second end of the valve member being connected with the netted tube; a main tube which is a hollow tube and has a first tube, a second tube, a flange, a stop and a guide slot, the first tube being located in the second recess and defining a first chamber, a first gap being defined between an outer periphery of the first tube and an inner periphery of the second recess; a piston unit including a first piston and a second piston, the first piston having a third recess, a fourth recess, an air hole, an air slot and a seal ring, and the wall defining the fourth recess being movable in contact with an inner periphery of the first recess and movably sealing the inlet valve, the guide slot being located between the stop and the seal ring which movably seals and opens the guide slot, the guide slot communicating with the air hole and the air slot; and the second piston having a fifth recess, a sixth recess and a protrusion, the second piston being connected to the second tube; a link unit extending through the main tube and including a link which has a contact portion which is movably in contact with the protrusion of the second piston, an inlet being defined between the protrusion and the contact portion, the link unit being located in the second tube with a second gap defined between the second tube and the link unit; a resilient member mounted to the second tube and having one end contacting the flange; a cylinder unit connected to the cap and having a first cylinder and a second cylinder, a ring located between the first and second cylinders (91 & 92) with the first piston being repeatedly movable in the first cylinder and forming a sealed second chamber, the wall defining the third recess being movably in contact with an inner periphery of the first cylinder, with a fourth chamber defined between the third recess, the first recess and the cap; the second piston being repeatedly movable in the second cylinder and forming a sealed third chamber, and a valve in contact with a passage in the second cylinder, characterized in that:- the link unit includes a further link and an engaging portion, the further link is connected to the link having the contact portion by the engaging portion, and the further link has a contact neck which is movably in contact with the inner periphery of the first tube, with an outlet defined between the first tube and the contact neck. a press head connected with a cap; a netted tube having a first net, a second net and a hollow tube; a valve member having a first end and a second end, the first end of the valve member having a first recess, a second recess, an inlet valve and a release path, the second end of the valve member being connected with the netted tube; a main tube which is a hollow tube and has a first tube, a second tube, a flange, a stop and a guide slot, the first tube being located in the second recess and defining a first chamber, a first gap being defined between an outer periphery of the first tube and an inner periphery of the second recess; a piston unit including a first piston and a second piston, the first piston having a third recess, a fourth recess, an air hole, an air slot and a seal ring, and the wall defining the fourth recess being movable in contact with an inner periphery of the first recess and movably sealing the inlet valve, the guide slot being located between the stop and the seal ring which movably seals and opens the guide slot, the guide slot communicating with the air hole and the air slot; and the second piston having a fifth recess, a sixth recess and a protrusion, the second piston being connected to the second tube; a link unit extending through the main tube and including a link which has a contact portion which is movably in contact with the protrusion of the second piston, an inlet being defined between the protrusion and the contact portion, the link unit being located in the second tube with a second gap defined between the second tube and the link unit; a resilient member mounted to the second tube and having one end contacting the flange; a cylinder unit connected to the cap and having a first cylinder and a second cylinder, a ring located between the first and second cylinders (91 & 92) with the first piston being repeatedly movable in the first cylinder and forming a sealed second chamber, the wall defining the third recess being movably in contact with an inner periphery of the first cylinder, with a fourth chamber defined between the third recess, the first recess and the cap; the second piston being repeatedly movable in the second cylinder and forming a sealed third chamber, and a valve in contact with a passage in the second cylinder, characterized in that:- the link unit includes a further link and an engaging portion, the further link is connected to the link having the contact portion by the engaging portion, and the further link has a contact neck which is movably in contact with the inner periphery of the first tube, with an outlet defined between the first tube and the contact neck.