Check method of worm gears comprising the following steps: - identification of a real profile of a gear to be checked, considering a plane that contains the axis of the gear, wherein the real profile is given by the intersection of the external lateral surface of the gear with the plane that contains the axis of the gear, - scanning of the real profile by means of a feeler, in such a way to obtain a measured profile, - filtering of the measured profile with a low pass filter with a preset cut-off frequency (fs), in such a way to obtain a primary profile, - filtering of the primary profile with a high pass filter with a preset cut-off frequency (fc), in such a way to obtain a surface analysis profile, - calculation of a median line of the surface analysis profile, - calculation of a first error quadratic average parameter (SA a) with the following expression: SA a = ∑ i x i np wherein xi are the absolute deviations of the points of the surface analysis profile from the median line of the surface analysis profile; and np is the number of points considered in the assessment analysis; - calculation of a second quadratic error parameter (SA q) with the following expression SA q = ∑ i x i 2 - calculation of a third peak average parameter (SA p) with the expression SA p = ∑ i p i np wherein p i are the peak points, whose distance from the median line of the surface analysis profile is higher than the distances of at least four adjacent points; - comparison of said first, second and third parameter (SA a; SA q; SA p) with corresponding preset threshold values (TSa; TSq; TSp) in such a way to reject the gear when at least one of said parameters exceeds the corresponding threshold value. - identification of a real profile of a gear to be checked, considering a plane that contains the axis of the gear, wherein the real profile is given by the intersection of the external lateral surface of the gear with the plane that contains the axis of the gear, - scanning of the real profile by means of a feeler, in such a way to obtain a measured profile, - filtering of the measured profile with a low pass filter with a preset cut-off frequency (fs), in such a way to obtain a primary profile, - filtering of the primary profile with a high pass filter with a preset cut-off frequency (fc), in such a way to obtain a surface analysis profile, - calculation of a median line of the surface analysis profile, - calculation of a first error quadratic average parameter (SA a) with the following expression: SA a = ∑ i x i np wherein xi are the absolute deviations of the points of the surface analysis profile from the median line of the surface analysis profile; and np is the number of points considered in the assessment analysis; xi are the absolute deviations of the points of the surface analysis profile from the median line of the surface analysis profile; and np is the number of points considered in the assessment analysis; - calculation of a second quadratic error parameter (SA q) with the following expression SA q = ∑ i x i 2 - calculation of a third peak average parameter (SA p) with the expression SA p = ∑ i p i np wherein p i are the peak points, whose distance from the median line of the surface analysis profile is higher than the distances of at least four adjacent points; - comparison of said first, second and third parameter (SA a; SA q; SA p) with corresponding preset threshold values (TSa; TSq; TSp) in such a way to reject the gear when at least one of said parameters exceeds the corresponding threshold value.