The staples thesis is a theory of Canadian economic development. It was first proposed by W.A. Mackintosh and was later expanded by Harold Innis.

Innis argues that Canada developed as it has because of certain staple commodities. These staples were raw materials that would then be exported to Europe. This close trading link would cement Canada's cultural links to the Europe. The search for and exploitation of these staples lead to the creations of institutions and the political culture of the nation and its regions.

Innis argues that differing staples create a different society. For instance the staple commodity in the Maritimes was the cod fishery. This industry was very decentralized, but also very co-operative. In western Canada the central staple was wheat farming. This was a very independent venture that has lead to a history of distrust of government and corporations in that part of the country. Also important, however, were the shocks caused by volatility in the market for wheat and by the weather itself on the growing season. In Central Canada the main staple was fur and the fur trade dominated the economy for many years. This fur trade was dominated by large firms, such as the Hudson's Bay Company and thus produced the much more centralized businesss oriented society found in Montreal and Toronto. To Innis it was the fur trade that created Canada, the early links of the fur traders from western forests to Eastern ports were the origins of Canadian unity and distinctiveness from the United States.

While the staples thesis was originally designed to describe Canada, it has since then been used to study the economies of many nations that are dependent upon resource extraction and primary industries.