Sojitz Corporation (Japanese: 双日株式会社, Hepburn: Sōjitsu Kabushiki-gaisha) is a sogo shosha (general trading company) based in Tokyo, Japan. It is engaged in a wide range of businesses globally, including buying, selling, importing, and exporting goods, manufacturing and selling products, providing services, and planning and coordinating projects, in Japan and overseas. Sojitz also invests in various sectors and conducts financing activities. The broad range of sectors in which Sojitz operates includes automobiles, energy, mineral resources, chemicals, foodstuff resources, agricultural and forestry resources, consumer goods, and industrial parks.

Sojitz was formed in 2004 by the merger of Nissho Iwai Corporation (日商岩井株式会社, Nisshō Iwai Kabushiki-gaisha) and Nichimen Corporation (ニチメン株式会社, Nichimen Kabushiki-gaisha). The name "Sojitz" is derived from the names of Nissho Iwai and Nichimen, both of which include the character "日" (sun). "Sojitz", literally meaning "twin suns", implies a merger of equals between the two companies. The corporate logo is a stylized version of the first character in its Japanese name.

Beginning around 1878, the Japanese government promoted the development of cotton spinning as an initial means of developing modern industry in Japan in the wake of the Meiji Restoration. Japan's native raw cotton supply proved inadequate to meet demand, and there was only one Japanese importer of raw cotton at the time, making the industry highly reliant on foreign merchants. To improve this situation, a group of spinning companies established Japan Cotton Trading Co., Ltd. (日本綿花株式会社, Nippon Menka Kabushiki Kaisha) in Osaka in 1892 under the leadership of Tsuneki Sano, a 38-year-old former government official.

After the Russo-Japanese War, Nichimen expanded its business from importing. The company began cotton spinning operations in the Kwantung Leased Territory and established offices in China, Korea, Germany, Italy and the United Kingdom to supply local markets. In 1910, Nichimen opened a subsidiary in Fort Worth, Texas to enter the raw cotton trade in the United States. World War I strained cotton supply in Europe, boosting Nichimen's international business further. In the late 1910s the company expanded into South America and Africa, trading in cotton as well as wool, food products, and machinery.

The Great Depression harmed Nichimen's cotton business, spurring the company's diversification beyond cotton to trade in silk, rayon and other materials. During World War II, Nichimen was tapped by the Japanese military to manage production of flour, matches and starch. The company changed its name to Nichimen Enterprise (Nichimen Jitsugyo) in 1943 to reflect its more diverse business.

The largest zaibatsu trading companies were dismantled after the war, giving Nichimen an early lead among the sogo shosha in the 1950s and a six percent share of Japanese foreign trade by 1958. Nichimen became closely affiliated with Osaka-based Sanwa Bank in 1955, which financed all of Nichimen's domestic business. Nichimen was not the main trading company for the Sanwa keiretsu as that position was already held by Iwai & Co. Nichimen Jitsugyo.

By 1970, Nichimen was trading in steel, electronics, motor vehicles and fibers in addition to textiles. Nichimen served as the joint venture partner for Nabisco when it began operations in Japan in the 1970s. Nichimen Co., Ltd. changed its name to Nichimen Corporation in 1982. Nichimen, like other sogo shosha, was hit hard by the collapse of the Japanese asset price bubble in the early 1990s, and subsequently made a strategic shift from the "soft" businesses of lumber, food, and chemicals trading to the "hard" businesses of machinery, steel, and construction.

Nissho Iwai was formed in 1968 by the merger of Nissho Company and Iwai Sangyo Company.