The Mercedes-Benz O405 is a single-decker bus manufactured by Mercedes-Benz from the mid-1980s to the early 2000s as either an integral bus or a bus chassis; it was the last VöV SL-II standard bus in production. It replaced the O305 and was widely used in Europe, the United Kingdom, Australia and Singapore with 12,000 produced.

Mercedes-Benz has been producing buses since 1895 in Mannheim in Germany. Since 1995 Mercedes-Benz buses and coaches is a brand of EvoBus GmbH, a wholly owned subsidiary of Daimler Truck.