The National Union of Railwaymen was a trade union of railway workers in Great Britain. It was established in 1913 as an amalgamation of the Amalgamated Society of Railway Engineers, the General Railway Workers' Union, and the United Pointsmen and Signalmen's Society. It catered for the majority of railway workers, including catering and maintenance, but not for members of the Associated Society of Locomotive Engineers and Firemen, (ASLEF), or the Railway Clerks' Association (RCA).

In 1914, the NUR joined forces with the National Transport Workers' Federation and Mining Federation of Great Britain to form the Triple Alliance.

In 1990, it joined with the National Union of Seamen to form the National Union of Rail, Maritime and Transport Workers (RMT), and ceased to exist as a separate organisation.