The Albula Railway is a single track metre gauge railway line forming part of the so-called core network of the Rhaetian Railway (RhB), in the Canton of Graubünden, Switzerland. It links Thusis on the Hinterrhein (697 m (2,287 ft) above sea level) with the spa resort of St. Moritz in Engadine (1,774 m (5,820 ft) above sea level).

Construction of the Albula Railway was begun in September 1898, the opening took place on 1 July 1903, and the extension to St. Moritz commenced operations on 10 July 1904. With its 55 bridges and 39 tunnels, the 61.67 km (38.32 mi) long line is one of the most spectacular narrow gauge railways in the world.

On 7 July 2008, the Albula Railway and the Bernina Railway, which also forms part of the RhB, were jointly recorded in the list of UNESCO World Heritage Sites, under the name Rhaetian Railway in the Albula / Bernina Landscapes.

The best known trains operating on the Albula Railway are the Glacier Express and the Bernina Express.

Up until 1890, the south east of Switzerland was extremely poorly served by railways. Alpine transit traffic was drawn to the Gotthard Railway, so that the construction of transcontinental railways in Graubünden appeared not to be economically viable. Only the success of the Landquart-Davos-Bahn (LD) led to a turning point. In 1895, the LD changed its name to Rhaetian Railway (RhB). Two years later, the people of Graubünden decided, in a referendum, that the RhB would come under state ownership. These two changes created suitable conditions for a rapid construction of further RhB lines, which were intended to open up large parts of the Canton.