James Gillespie Barclay (24 June 1882 – 5 October 1972) was a New Zealand politician of the Labour Party.
Barclay was born in Pigeon Bay on Banks Peninsula. His father was Morrison Barclay. He married Helen Betrice in 1907, but was a widower by the time he joined the army. Before World War I, he was a farmer and lived in the Christchurch suburb of Riccarton. He served with the New Zealand Expeditionary Force from 1916 to 1919. He then bought a property in Pukehuia, Northland, where he owned near the Wairoa River. He sold his farm in 1931 and retired to Whangarei. He served on several local boards in Northland.
Barclay unsuccessfully stood against the Prime Minister, Gordon Coates, in the electorate in the . In the , he unsuccessfully challenged the incumbent in the electorate in Northland, Alfred Murdoch. He beat Murdoch in the , but was defeated in turn by Murdoch after two parliamentary terms in 1943.
He was a