The present invention discloses an anti-ultraviolet low-smoke fire retardation ABS resin for school buses, and a preparation method thereof. The anti-ultraviolet low-smoke fire retardation ABS resin is prepared from the following components, by weight: 50-70 parts of an acrylonitrile-butadiene-styrene copolymer (ABS resin), 10-40 parts of an auxiliary resin, 3-20 parts of a composite main fire retardation agent, 5-20 parts of an auxiliary fire retardation agent, 3-10 parts of a smoke inhibitor, 0-1 part of an antioxidant, 0.1-2 parts of an anti-ultraviolet agent, and 0.1-3 parts of a coupling agent. The anti-ultraviolet low-smoke fire retardation ABS resin has a good anti-ultraviolet performance in the case of no influence on comprehensive mechanical properties, has characteristics of low smoke formation and good fire retardation during burning, and is especially for molding of various decorations of school buses.