The South Devon Railway 0-4-0 locomotives were small 0-4-0 broad gauge locomotives operated on the South Devon Railway, Cornwall Railway, mainly on the dockside lines around Plymouth. On 1 February 1876 the South Devon Railway was amalgamated with the Great Western Railway, the locomotives were given numbers by their new owners but continued to carry their names too.

Tiny

Tiny was built by Sara and Company. It has a vertical boiler and was similar to four locomotives that later worked in the docks at Falmouth in Cornwall. After withdrawal it was used at Newton Abbot where it was used to power machinery in the workshops there. In 1927, no longer required for this purpose, it was displayed on the platform at the station opposite the workshops. It has since been moved to Buckfastleigh railway station where it is displayed in the museum of the South Devon Railway Trust. Tiny is the last surviving locomotive originally built to Brunel's 7 ft 0 1⁄4 in (2140 mm) broad gauge.

Owl class

The three Owl class locomotives had well tanks and were built by the Avonside Engine Company.

Raven class

The seven Raven class were saddle tank locomotives and were again built by the Avonside Engine Company. They were highly unusual for broad gauge locomotives in having outside cylinders.