John Duncan McArthur (June 25, 1854 – January 10, 1927) was an important Canadian industrialist and railway builder. He built lines in Manitoba, Saskatchewan, and Alberta. He also was principal in many hotels, lumber and fuel companies.

After 74 years of a long prosperous life McArthur died just after arriving on a train from Battle Creek, Michigan, to Winnipeg in a private train car supplied by Michigan Central Railway. He had been undergoing treatments for acute anemia. After being educated at a local school and spending much of his childhood at his father's farm he travelled west in 1879 where he began his career in the railroad business. He returned east to marry his childhood sweetheart, Mary McIntosh, in 1889. In 1901, McArthur decided to invest in a saw mill and brick factory. However, it was not until 1906 that he took on the major job of constructing 400 km (250 mi) of the Grand Trunk Pacific Railway. Four years later McArthur almost went bankrupt on the construction of the Edmonton, Dunvegan and British Columbia Railway. He tried to build an extensive system in Alberta, the Edmonton, Dunvegan and British Columbia Railway, which was hampered by the First World War. "He was one of western Canada’s greatest railway contractors, having built over 2,833 miles [4,559 km] of track, but he was also one of its most controversial."