Reuben J. Waugh was a politician in Manitoba, Canada. He served in the Legislative Assembly of Manitoba from 1920 to 1922 as a member of the Conservative Party. Waugh resided in Carberry, Manitoba during his time in the legislature.
He was elected to the Manitoba legislature in the 1920 provincial election, defeating incumbent Liberal John Graham by 217 votes in the Norfolk constituency. The Liberals won a minority government in this election, and Waugh sat with his party on the opposition benches. He was defeated in the 1922 election, losing to John Muirhead of the United Farmers of Manitoba by 135 votes.
Waugh attempted to return to the legislature in the 1927 election, but lost to Muirhead by only 34 votes. He challenged Muirhead again in the 1932 election, and this time lost by 236 votes.