A method for monitoring a state of a blood line (3) in a circuit (2) for extracorporeal blood treatment, comprising steps of: acquiring at least a first pressure value from a first sensor (13, 19) mounted at a first point of a circuit (2) for extracorporeal blood treatment, comprising a blood line (3) in which the blood is subjected to a pulsating thrust; acquiring at least a second pressure value from a second sensor (14) mounted at a second point, distinct from the first point of the blood line (3) of the circuit (2) for extracorporeal blood treatment, and correlating at least a first value, correlated to the first pressure value, and at least a second value, correlated to the second pressure value, with at least a threshold value, in order to obtain a datum representing a state of the blood line (3).