Device for determining the angular speed of a bicycle wheel and the pedaling cadence applied by a user to the pedals of said bicycle, said device comprising: - a sensor of said angular speed of the bicycle wheel, adapted to be coupled to said bicycle wheel, suitable for detecting said angular speed of the bicycle wheel (ω i) and for generating a signal representative of said angular speed of the bicycle wheel, wherein said sensor of the angular speed of the bicycle wheel comprises: a moving part, adapted to be rotatively integral with the wheel of the bicycle and provided with a plurality of reference elements integral with the moving part; a fixed part adapted to be associated to the bicycle frame, comprising means for detecting the transits of said reference elements near the detecting means and for generating a signal representing said transits; a control module configured for determining said angular speed of the bicycle wheel (ω i) and for generating said signal representing the angular speed of the bicycle wheel, based on said signal representing said transits; - a filter connected to said sensor of the angular speed of the bicycle wheel, configured for receiving at the input said signal representative of the angular speed of the bicycle wheel (ω i) and for supplying at the output an optimized signal (ω opt) of the angular speed of the bicycle wheel obtained by eliminating from the signal representative of the angular speed of the bicycle wheel (ω i) estimated errors (θ i) correlated to the structure of said sensor of the angular speed of the bicycle wheel, wherein said filter is configured for estimating an angular error (θ̂ i) for each couple of reference elements of said plurality of reference elements integral with the moving part of the angular speed sensor from said signal representing the angular speed of the wheel (ω i) and from an average speed ω ^ i 0 estimated based on the time of revolution Δ t i rev of said couple of reference elements, the optimized signal of the the angular speed of the bicycle wheel (ω opt) being obtained from said estimated angular error ( θ̂ i); - a module for the frequency analysis of said optimized signal (ω opt) of the angular speed of the bicycle wheel connected to said filter, configured for determining said pedaling cadence based on the frequency analysis of said optimized signal (ω opt) of the angular speed of the bicycle wheel and for supplying a signal representative of said pedaling cadence. - a sensor of said angular speed of the bicycle wheel, adapted to be coupled to said bicycle wheel, suitable for detecting said angular speed of the bicycle wheel (ω i) and for generating a signal representative of said angular speed of the bicycle wheel, wherein said sensor of the angular speed of the bicycle wheel comprises: a moving part, adapted to be rotatively integral with the wheel of the bicycle and provided with a plurality of reference elements integral with the moving part; a fixed part adapted to be associated to the bicycle frame, comprising means for detecting the transits of said reference elements near the detecting means and for generating a signal representing said transits; a control module configured for determining said angular speed of the bicycle wheel (ω i) and for generating said signal representing the angular speed of the bicycle wheel, based on said signal representing said transits; - a filter connected to said sensor of the angular speed of the bicycle wheel, configured for receiving at the input said signal representative of the angular speed of the bicycle wheel (ω i) and for supplying at the output an optimized signal (ω opt) of the angular speed of the bicycle wheel obtained by eliminating from the signal representative of the angular speed of the bicycle wheel (ω i) estimated errors (θ i) correlated to the structure of said sensor of the angular speed of the bicycle wheel, wherein said filter is configured for estimating an angular error (θ̂ i) for each couple of reference elements of said plurality of reference elements integral with the moving part of the angular speed sensor from said signal representing the angular speed of the wheel (ω i) and from an average speed ω ^ i 0 estimated based on the time of revolution Δ t i rev of said couple of reference elements, the optimized signal of the the angular speed of the bicycle wheel (ω opt) being obtained from said estimated angular error ( θ̂ i); - a module for the frequency analysis of said optimized signal (ω opt) of the angular speed of the bicycle wheel connected to said filter, configured for determining said pedaling cadence based on the frequency analysis of said optimized signal (ω opt) of the angular speed of the bicycle wheel and for supplying a signal representative of said pedaling cadence.