Industrial Revolution enticed the industrial countries to merge overseas countries with world economy in order to meet their needs. These countries intended to make overseas countries a market for their industrial products and to supply their raw materials from such countries. For this purpose, in 19th century the capitalist societies, with two policies of establishing colonial territories and imposing commercial, customs and legal treaties with political force, tried to merge overseas countries with world economy. Iran was no exception. Therefore, this article intends to conduct a historical research and to pose the question of what were the proofs and indications of Iran’s merger with world economy in 19th century. The results of this research show that Iran was merged into world economy with the mechanism of forced commercial, customs, and legal contracts. This merger in 19th century, especially in the second half, had two indications. The first one was a change in Iran’s economic agricultural production from livelihood agriculture to a commercial one with the purpose of exporting raw materials of agriculture to the world market. The second one was the daily growth of imported consumer goods that paved the way for making Iran a market for such goods.