Equipment for controlling blood flow in an extra-corporeal blood circuit, comprising at least a first sensor (11), de-signed to measure an arterial pressure (Part) upstream of a peristaltic pump (9); at least a second sensor (12), designed to measure an angular velocity (.OMEGA.) of the peristaltic pump; a memory (14) de-signed to store at least one set value (Qset) of the desired blood flow through the access branch, and a calibration function (F) in at least the variables (vI), related to the angular velocity (.OMEGA.) of the pump, (v2), related to the arterial pressure (Part) in the portion of the said access branch upstream of the peristaltic pump, (v3), related to an actual flow of blood (Qactual) through the said access branch; and at least one control unit (13), capable of calculating an actual flow value (Qactual) by applying the function F to the values of angular velocity and arterial pressure (Part, .OMEGA.) measured by the sensors; comparing the actual flow (Qactual) with the desired flow (Qset); and varying the angular velocity of the said peristaltic pump if the Qactual--Qset lies outside a predetermined range.