601051 Disclosed is a method of detecting a flow of milk (8) in a milk line (2). The milk line (2) is connected to a teat cup (3) having a pulsator space (6) and which has an aeration opening (5) such that the milk (8) defines a filling level in a measuring section (7) of the milk line (2). A milking vacuum is applied in the milk line (2), and a pulsating vacuum is applied in the pulsator space (6) of the teat cup (3). The filling level of the milk (8) is measured in the measuring section (7) at least during a first period of time (&Dgr；t). A variation is determined of the filling level measured at least during the first period of time (&Dgr；t) in the form of an indicator number which is then compared with a predetermined threshold value. The threshold value is indicative of the presence or absence of a flow of milk (8) in the milk line (2).
