John Lineham (21 March 1857 – 21 April 1913) was a territorial-level politician from Northwest Territories, Canada.Lineham was elected to the Legislative Assembly of the Northwest Territories in the 1888 Northwest Territories general election. He won the top place in the two-man district of Calgary. There were three candidates running for the two seats. Hugh Cayley was returned to the legislature as the second-place candidate.