An extracorporeal blood treatment apparatus, comprising: an extracorporeal blood circuit having a treatment unit, a blood withdrawal line connected to a blood inlet of the treatment unit, and a blood return line connected to a blood outlet of the treatment unit; a blood pump configured for controlling blood flow rate (Q BLOOD) flowing through at least one of said blood withdrawal line and blood return line; at least one infusion line (15, 21, 25) connected to the extracorporeal blood circuit; a warming device configured to heat a blood heating zone of the extracorporeal blood circuit; a control unit configured to execute the following procedure: - receiving a first value representative of a desired blood temperature (T des) at an end of the blood return line configured to be connected to a venous vascular access of a patient; - receiving at least a first signal relating to at least a flow rate (Q PBP, Q REP1, Q REP2) of an infusion fluid in said at least one infusion line (15, 21, 25); - calculating a set point value of an operating parameter (T OUT; P w) to be imposed on the warming device configured to heat the blood heating zone of the extracorporeal blood circuit in order to maintain said desired blood temperature (T des) at said end of the blood return line; wherein the set point is calculated based on input parameters comprising: ∘ at least the first value representative of the desired blood temperature (T des) and ∘ at least one selected in the group of: ▪ the first signal (Q REP1, Q PBP, Q REP2) and ▪ a second value representative of a temperature (T REP1, T PBP, T REP2) of said at least one infusion fluid in said at least one infusion line (15, 21, 25); wherein the warming device is located on the blood return line or on the blood withdrawal line and configured to directly heat the blood heating zone. an extracorporeal blood circuit having a treatment unit, a blood withdrawal line connected to a blood inlet of the treatment unit, and a blood return line connected to a blood outlet of the treatment unit; a blood pump configured for controlling blood flow rate (Q BLOOD) flowing through at least one of said blood withdrawal line and blood return line; at least one infusion line (15, 21, 25) connected to the extracorporeal blood circuit; a warming device configured to heat a blood heating zone of the extracorporeal blood circuit; a control unit configured to execute the following procedure: - receiving a first value representative of a desired blood temperature (T des) at an end of the blood return line configured to be connected to a venous vascular access of a patient; - receiving at least a first signal relating to at least a flow rate (Q PBP, Q REP1, Q REP2) of an infusion fluid in said at least one infusion line (15, 21, 25); - calculating a set point value of an operating parameter (T OUT; P w) to be imposed on the warming device configured to heat the blood heating zone of the extracorporeal blood circuit in order to maintain said desired blood temperature (T des) at said end of the blood return line; wherein the set point is calculated based on input parameters comprising: ∘ at least the first value representative of the desired blood temperature (T des) and ∘ at least one selected in the group of: ▪ the first signal (Q REP1, Q PBP, Q REP2) and ▪ a second value representative of a temperature (T REP1, T PBP, T REP2) of said at least one infusion fluid in said at least one infusion line (15, 21, 25); - receiving a first value representative of a desired blood temperature (T des) at an end of the blood return line configured to be connected to a venous vascular access of a patient; - receiving at least a first signal relating to at least a flow rate (Q PBP, Q REP1, Q REP2) of an infusion fluid in said at least one infusion line (15, 21, 25); - calculating a set point value of an operating parameter (T OUT; P w) to be imposed on the warming device configured to heat the blood heating zone of the extracorporeal blood circuit in order to maintain said desired blood temperature (T des) at said end of the blood return line; wherein the set point is calculated based on input parameters comprising: ∘ at least the first value representative of the desired blood temperature (T des) and ∘ at least one selected in the group of: ▪ the first signal (Q REP1, Q PBP, Q REP2) and ▪ a second value representative of a temperature (T REP1, T PBP, T REP2) of said at least one infusion fluid in said at least one infusion line (15, 21, 25); ∘ at least the first value representative of the desired blood temperature (T des) and ∘ at least one selected in the group of: ▪ the first signal (Q REP1, Q PBP, Q REP2) and ▪ a second value representative of a temperature (T REP1, T PBP, T REP2) of said at least one infusion fluid in said at least one infusion line (15, 21, 25); ▪ the first signal (Q REP1, Q PBP, Q REP2) and ▪ a second value representative of a temperature (T REP1, T PBP, T REP2) of said at least one infusion fluid in said at least one infusion line (15, 21, 25);