A protective helmet comprising: - a shell having a longitudinal plane of symmetry and comprising a face opening and left and right side portions, a slide being arranged in each of the side portions of the shell, the slides being symmetrical relative to the longitudinal plane of symmetry; - a face-shield mounted on the shell and moveable between a lowered position in which the face-shield extends opposite the face opening and a raised position in which the face opening is substantially bared, the face-shield comprising a central portion and two side wings, at least one connecting member (16, 17) being arranged on each side wing of the face-shield so that it can be engaged in the corresponding slide of the shell, and so that it can slide in said slide to guide the movement of the face-shield between its lowered and raised positions, characterized in that: - the face-shield is mounted inside the shell; - on each side wing, the face-shield comprises at least one upper connecting member and one lower connecting member which project outwardly from the side wings of the face-shield; - and each slide comprises: - an upper part intended to receive the upper connecting member, the said upper part of the slide extending generally horizontally, in the position of use, and having a curved shape with the concavity directed downwardly; - and a lower part intended to receive the lower connecting member, the said lower part of the slide having at least one main portion which generally extends vertically, in the position of use, and which has a curved shape with the concavity directed towards the rear. - a shell having a longitudinal plane of symmetry and comprising a face opening and left and right side portions, a slide being arranged in each of the side portions of the shell, the slides being symmetrical relative to the longitudinal plane of symmetry; - a face-shield mounted on the shell and moveable between a lowered position in which the face-shield extends opposite the face opening and a raised position in which the face opening is substantially bared, the face-shield comprising a central portion and two side wings, at least one connecting member (16, 17) being arranged on each side wing of the face-shield so that it can be engaged in the corresponding slide of the shell, and so that it can slide in said slide to guide the movement of the face-shield between its lowered and raised positions, - the face-shield is mounted inside the shell; - on each side wing, the face-shield comprises at least one upper connecting member and one lower connecting member which project outwardly from the side wings of the face-shield; - and each slide comprises: - an upper part intended to receive the upper connecting member, the said upper part of the slide extending generally horizontally, in the position of use, and having a curved shape with the concavity directed downwardly; - and a lower part intended to receive the lower connecting member, the said lower part of the slide having at least one main portion which generally extends vertically, in the position of use, and which has a curved shape with the concavity directed towards the rear. - an upper part intended to receive the upper connecting member, the said upper part of the slide extending generally horizontally, in the position of use, and having a curved shape with the concavity directed downwardly; - and a lower part intended to receive the lower connecting member, the said lower part of the slide having at least one main portion which generally extends vertically, in the position of use, and which has a curved shape with the concavity directed towards the rear.