A lens system and a camera, where the lens system includes a first refractive element, a second refractive element, a reflecting element, and a photosensitive element, where the first refractive element and the reflecting element are disposed along a direction of a first optical axis, the second refractive element and the reflecting element are disposed along a direction of a second optical axis, the first optical axis is perpendicular to the second optical axis, the second refractive element and the photosensitive element are disposed in parallel, an effective aperture diameter of the first refractive element is greater than an effective aperture diameter of the second refractive element in a height direction of the lens system, and the first optical axis is parallel to the height direction of the lens system.