The invention relates to a releasable blocking system (1) of a catheter (4), comprising a base (2) adapted to receive a catheter (4), and a shell (3), mounted in rotation on the base (2) between an open position, in which the shell (3) is away from the base (2), and a closed position, in which the shell (3)is hooked on the base (2) and blocks the catheter (4) in position, in which:the system comprises an actuator (25) provided with a guide aperture (251), mobile in a housing (20) between a rest position and a blocking position, the actuator (25) comprising a first drive element (255),the shell (3)comprises a second drive element (33), adapted to cooperate with the first drive element (255) when the shell (3) is shifted from its open position to its closed position, and shift the actuator (25) to its blocking position.
