The Dolphinton Branch refers to two railway branch lines in Lanarkshire and Peeblesshire, Scotland, built in the nineteenth century.
The first was built by the nominally independent Leadburn, Linton and Dolphinton Railway. It opened in 1864 and was soon absorbed by the North British Railway, becoming that company's Dolphinton Branch. The second was built by the Caledonian Railway, and it opened in 1867. The population of Dolphinton then was 260, and the primary purpose of the lines was to secure territory, rather than to serve the small local community.
Each line had its own terminal station. The North British Railway line to Dolphinton closed in 1933, though the Leadburn to Macbie Hill section reopened in 1939 to serve an army camp and remained open until 1960. The Caledonian line closed to passengers in 1945 and to goods in 1950. There is now no railway activity on the lines.