A device for regulating the flow rate of a medical liquid comprises a body (2) provided with elements (6, 8) associated with corresponding parts (3, 4) connected together but torsionally free, at least one (4) of said parts (3, 4) comprising a plurality of recesses (25) acting as flow regulator means able to modify the flow rate of said liquid directed towards the patient by rotating said parts about a common axis of rotation (K), between said parts (3, 4) a seal element (10) enables said recesses (25) to be selectively connected together via communication means (30, 31), so achieving said flow rate regulation. Transverse sealing means (38 51 57,- 61) are provided between said seal element (10) and at least the second part (4) of said parts (3, 4) which are interconnected but torsionally free, said transverse sealing means (38, 51, 57, 61) preventing the escape of liquid from said recesses (25) and from the body (2) of the device (1) following a relative movement or misalignment between said parts (3, 4) in a plane perpendicular to said axis of rotation (K) or along this latter during flow regulation or following any angular misalignment of said parts (3, 4) relative to said axis (K).Linvention concerne un dispositif de régulation du débit dun liquide médical administré à un patient, ce dispositif comprenant un corps (2) pourvu déléments (6, 8) raccordés à des conduits reliés respectivement à un réservoir de liquide et au patient. Ces éléments (6, 8) sont associés à des pièces correspondantes (3, 4) reliées ente elles, mais sans torsion, au moins une (4) de ces pièces (3, 4) comprenant une pluralité dévidements (25) agissant comme des moyens de régulation de lécoulement capables de modifier le débit du liquide administré au patient par rotation des pièces autour dun axe de rotation commun (K). Entre les pièces (3, 4) est placé un élément détanchéité 810) qui permet de raccorder sélectivement les évidements (25) entre eux par des moyens de communication (30, 31) de f
