An infusion control device controls infusion of a liquid in an extracorporeal blood circuit having an arterial pipe connected to an inlet of a blood compartment of a filter and a venous pipe connected to an outlet of the blood compartment. The arterial pipe is also connected to a pre-dilution pipe of an infusion circuit, and the venous pipe is also connected to a post-dilution pipe of said infusion circuit. The infusion control device regulates and distributes an infusion flow rate in the arterial and venous pipes based on a monitoring of quantities that are directly correlated with the operating conditions of the filter.