Method for inspecting cylinder-shaped elongated elements for smoking articles, comprising the following steps: selecting a working plane passing through a longitudinal axis (S') of a first elongated element and considering a first half-space and a second half-space arranged on opposite parts with respect to the working plane; in an operating step of the inspection method, projecting on an external face of the first elongated element a first stripe of light from the first half-space and obtaining a first three-dimensional light trace on an inspection portion of the external face, projecting a second stripe of light from the second half-space on the inspection portion and obtaining a second three-dimensional light trace; processing a first view of the first elongated element, the first view being obtained by framing the first elongated element from the first half-space and identifying in the first view a respective first curved line; processing a second view of the first elongated element, the second view being obtained by framing the first elongated element from the second half-space, and identifying in the second view a respective second curved line; reconstructing a first closed curved section profile of the first elongated element by processing the first identified curved line and the second identified curved line, characterized in that the method further comprises comparing the reconstructed first closed curved profile with an ideal closed section profile, to identify possible deformations of the reconstructed first closed curved profile with respect to the ideal section profile; wherein the method comprises arranging in a reference position an ideal elongated element alongside the first elongated element, arranged in a first position, such that the longitudinal axis (S') of the first elongated element and a longitudinal axis (S"') of the ideal elongated element are arranged in the working plane; inspecting simultaneously the first elongated element and the ideal elongated element by the first stripe of light and the second stripe of light; obtaining from the projection of the first stripe of light a first three-dimensional light trace on an external face of the ideal elongated element and obtaining from the projection of the second stripe of light a second three-dimensional light trace on the external face of the ideal elongated element; framing simultaneously from the first half-space the first elongated element and the ideal elongated element so as to process the first view to identify additionally a first curved line of the ideal elongated element; framing simultaneously from the second half-space the first elongated element and the ideal elongated element such as to process the second view to identify additionally a second curved line of the ideal elongated element; reconstructing a closed curved section profile of the ideal elongated element by processing the first identified curved line and the second identified curved line; monitoring the reconstructed closed curved profile of the ideal elongated element generating a warning if the reconstructed closed curved profile of the ideal elongated element is different from an ideal section profile; wherein reconstructing the first closed curved profile comprises the following steps: arranging facing each other the first identified curved line and the second identified curved line; applying a first geometric transformation to the first identified curved line and to the second identified curved line arranged facing each other to calculate the first closed curved section profile from the perspectively corrected first curved line (7") and from the perspectively corrected second line (10"); calculating in a calibration step, preceding the operating step, the first geometric transformation applied during the operating step, in which calculating the first geometric transformation comprises the following steps: using the ideal elongated element and arranging the ideal elongated element instead of the first elongated element in the first position, wherein the method further includes the step of calculating in the calibration step a reference geometric transformation associated with the reference position, using the ideal elongated element present in the reference position; and further comprising the step of inspecting in the operating step the first elongated element in the first position and the ideal elongated element in the reference position using for both the reference geometric transformation to auto-configure the inspection method if the reconstructed closed curved profile of the ideal elongated element is different from the ideal section profile.