Method for detecting the ruminal motility of farm animals, which comprises: a step for applying an accelerometer (1) at the fossa of one side of a ruminant animal; a step for detecting a time series of acceleration measurements (Xa, Ya, Za), carried out by means of the accelerometer (1); a step for discrimination in order to obtain, from the aforesaid acceleration measurements (Xa, Ya, Za), a selection group of such acceleration measurements (Xa, Ya, Za) detected in a first time interval (Tl) and indicative of a first behavior condition of the animal, such as a decubitus condition of the animal; a step for processing the acceleration measurements (Xa, Ya, Za) detected in the aforesaid first time interval (Tl), which calculates corresponding parameters of ruminal motility (PM) indicative of the detection of ruminal contractions of the animal.
