Device for detecting railway equipment defects, comprising: - at least three diagnostic modules mounted on a generic railway vehicle, of which: - a first module, called geometrical module, is configured to measure at least a geometrical feature of the railway; - a second module, called acceleration module, is configured to measure in at least a point of said vehicle the lateral and/or vertical accelerations transmitted from the railway to said vehicle; - a third module, called visual module, is configured to acquire images of railway elements and to analyze them to verify the presence of anomalies; - means for detecting the position of the railway vehicle; - electronical means configured to acquire data detected by said diagnostic modules and to calculate, for each detection carried out by each module, a severity index representative of the deviation of the detection with respect to the standard condition of the railway without defects, characterized in that said electronic means are configured to: a) calculate for each detection of each module an initial severity index (h 1) indicative of the amplitude of the deviation of the detection with respect to the standard condition without defects; b) associate to each initial severity index (h 1) a parameter (di) indicative of the kind of potential defect; c) associate each initial severity index (h 1) and respective parameter (di) indicative of the kind of potential defect with their acquisition position (x i), thus defining a potential defect having the characteristics of: a position (x i), a kind parameter (di) and an initial severity index (h 1); d) calculate for each potential defect defined in point c) a global severity index (ht), as a function of said parameter (di) indicative of the kind, of said initial severity index (h 1), and of the relative distances (xij) with respect to other detected potential defects, of their kind parameters and of their initial severity index; e) compare said global severity index (h t) with a critical threshold to determine if said potential defect needs a maintenance operation or not. - at least three diagnostic modules mounted on a generic railway vehicle, of which: - a first module, called geometrical module, is configured to measure at least a geometrical feature of the railway; - a second module, called acceleration module, is configured to measure in at least a point of said vehicle the lateral and/or vertical accelerations transmitted from the railway to said vehicle; - a third module, called visual module, is configured to acquire images of railway elements and to analyze them to verify the presence of anomalies; - a first module, called geometrical module, is configured to measure at least a geometrical feature of the railway; - a second module, called acceleration module, is configured to measure in at least a point of said vehicle the lateral and/or vertical accelerations transmitted from the railway to said vehicle; - a third module, called visual module, is configured to acquire images of railway elements and to analyze them to verify the presence of anomalies; - means for detecting the position of the railway vehicle; - electronical means configured to acquire data detected by said diagnostic modules and to calculate, for each detection carried out by each module, a severity index representative of the deviation of the detection with respect to the standard condition of the railway without defects, a) calculate for each detection of each module an initial severity index (h 1) indicative of the amplitude of the deviation of the detection with respect to the standard condition without defects; b) associate to each initial severity index (h 1) a parameter (di) indicative of the kind of potential defect; c) associate each initial severity index (h 1) and respective parameter (di) indicative of the kind of potential defect with their acquisition position (x i), thus defining a potential defect having the characteristics of: a position (x i), a kind parameter (di) and an initial severity index (h 1); d) calculate for each potential defect defined in point c) a global severity index (ht), as a function of said parameter (di) indicative of the kind, of said initial severity index (h 1), and of the relative distances (xij) with respect to other detected potential defects, of their kind parameters and of their initial severity index; e) compare said global severity index (h t) with a critical threshold to determine if said potential defect needs a maintenance operation or not.