The invention concerns a device (1) for dispensing a fluid (L), comprising a supporting structure (2) provided with means (3) for coupling it with a container (C) holding the fluid (L) and comprising: an outlet duct (63) for the fluid (L); a collapsible chamber (60); first valve means (25) suited to control the passage of the fluid; air refilling valve means. The air refilling valve means comprise a flexible portion (15) of an edge (14) belonging to a first element (10) of the device (1), suited to assume a closed position and an open position. The invention concerns also a system comprising a container and a device made as described above.