An obstacle detection system for a mobile apparatus, comprising: a structured light projection module configured to project structured light on a forward path of the mobile apparatus, the structured light comprising at least one lateral detection line in a horizontal direction and at least one longitudinal detection line in a vertical direction, wherein the structured light projection module projects a first lateral detection line according to a first preset angle range, projects a first longitudinal detection line according to a second preset angle range, the first longitudinal detection line being located above the first lateral detection line; a camera module configured to capture an image of the structured light; and an image processing module configured to calculate a distance and a position of an obstacle (106, 107, 108) on the forward path according to the image of the structured light, wherein the structured light projection module comprises a laser light source configured to emit a laser beam, and a diffractive optical element disposed downstream of an optical path of the laser light source to receive the laser beam and project the structured light, characterized in that the structured light projection module further projects a second lateral detection line according to a fourth preset angle range, the second lateral detection line being located below and parallel to the first lateral detection line, the structured light projection module further projects a second longitudinal detection line according to a third preset angle range, the second longitudinal detection line being located below the first lateral detection line and on an extension line of the first longitudinal detection line, and the first longitudinal detection line is spaced from the second longitudinal detection line. a structured light projection module configured to project structured light on a forward path of the mobile apparatus, the structured light comprising at least one lateral detection line in a horizontal direction and at least one longitudinal detection line in a vertical direction, wherein the structured light projection module projects a first lateral detection line according to a first preset angle range, projects a first longitudinal detection line according to a second preset angle range, the first longitudinal detection line being located above the first lateral detection line; a camera module configured to capture an image of the structured light; and an image processing module configured to calculate a distance and a position of an obstacle (106, 107, 108) on the forward path according to the image of the structured light, wherein the structured light projection module comprises a laser light source configured to emit a laser beam, and a diffractive optical element disposed downstream of an optical path of the laser light source to receive the laser beam and project the structured light, characterized in that the structured light projection module further projects a second lateral detection line according to a fourth preset angle range, the second lateral detection line being located below and parallel to the first lateral detection line, the structured light projection module further projects a second longitudinal detection line according to a third preset angle range, the second longitudinal detection line being located below the first lateral detection line and on an extension line of the first longitudinal detection line, and the first longitudinal detection line is spaced from the second longitudinal detection line.