An information providing device configured for a motorcycle , the information providing device comprising: an image acquisition section including a photographic lens and an imaging element that is arranged to capture an image of a road on which the motorcycle travels in front of the motorcycle ; a lane detection section that is arranged to detect at least one of a left lane and a right lane from the image of the road captured by the image acquisition section , and to detect from the captured image: a first value which is a radius of curvature of the at least one detected lane; and a second value which is a lateral distance from the motorcycle to the at least one lane; a motorcycle trajectory curvature calculation section that is arranged to calculate a radius of curvature of a motorcycle trajectory on the basis of the first value and the second value of the at least one lane; a vehicle speed (V) acquisition section that is arranged to acquire a vehicle speed (V) of the motorcycle ; a motorcycle physical quantity calculation section that is arranged to calculate a physical quantity related to a turn of the motorcycle which is derived from a balancing condition between a centrifugal force and weight of the motorcycle during the turn and is an inclination angle of the motorcycle with respect to vertical, on the basis of the radius of curvature of the motorcycle trajectory and the vehicle speed (V); a warning determination section that is arranged to determine whether a warning should be issued on the basis of the inclination angle of the motorcycle ; and a warning signal generation section that generates a warning signal when the warning determination section determines that the warning should be issued, wherein the warning should be issued when the inclination angle of the motorcycle exceeds a threshold inclination angle set for the vehicle speed. an image acquisition section including a photographic lens and an imaging element that is arranged to capture an image of a road on which the motorcycle travels in front of the motorcycle ; a lane detection section that is arranged to detect at least one of a left lane and a right lane from the image of the road captured by the image acquisition section , and to detect from the captured image: a first value which is a radius of curvature of the at least one detected lane; and a second value which is a lateral distance from the motorcycle to the at least one lane; a motorcycle trajectory curvature calculation section that is arranged to calculate a radius of curvature of a motorcycle trajectory on the basis of the first value and the second value of the at least one lane; a vehicle speed (V) acquisition section that is arranged to acquire a vehicle speed (V) of the motorcycle ; a motorcycle physical quantity calculation section that is arranged to calculate a physical quantity related to a turn of the motorcycle which is derived from a balancing condition between a centrifugal force and weight of the motorcycle during the turn and is an inclination angle of the motorcycle with respect to vertical, on the basis of the radius of curvature of the motorcycle trajectory and the vehicle speed (V); a warning determination section that is arranged to determine whether a warning should be issued on the basis of the inclination angle of the motorcycle ; and a warning signal generation section that generates a warning signal when the warning determination section determines that the warning should be issued, wherein the warning should be issued when the inclination angle of the motorcycle exceeds a threshold inclination angle set for the vehicle speed. <EOS>