Frank Robert Welsh (12 April 1871 – 28 December 1959) was an Australian politician who represented the Western Australian Legislative Assembly seat of Pilbara from 1933 until 1939, and one of the three Legislative Council seats for North Province from 1940 until 1954.
In 1891, he moved to Western Australia, and he married Amy Hancock on 4 November 1903 at Warralong Station near Marble Bar, in which he had acquired an interest and later became a managing partner.
At the 1933 state election, he contested the Labor-held seat of Pilbara, whose member Alfred Lamond had retired after three terms.
He won on a slightly increased margin in 1936, before being defeated in 1939 by Bill Hegney of the Labor Party.
He then stood for and won a North Province seat at the 1940 periodic elections for the Legislative Council, which he held for 14 years.