Among the factors determining grapes quality and yield, canopy volume and architecture are recognised to play a major role. Measurement methods able to evaluate the variability of canopy volume within the vineyard and the associated evolution during the growth season are then desirable for a Precision Viticulture (PV) practice. To this aim, many efforts have being devoted to apply remote sensing techniques which allow fast and large scale measurements can provide information about canopy density and, in particular, tractor mounted sensors can acquire, with no time-cost during ordinary field operations, high resolution data at different stages of grapevine development. Ultrasonic sensors, due to their low-cost and compactness, can be a suitable solution for a tractor mounted measurement system of canopy structure. The results of this study show a close relationship between the measurements obtained by ultrasound and the volumes of the canopies of vines