Tokyo possesses the largest metropolitan economy in the world with an estimated GDP of US$1,191 billion in 2005. Tokyo is a major international financial centre, is home to several of the world's largest investment banks and insurance companies, and is the hub for the national transportation, publishing, and broadcasting industries. The post-war growth of Japan's economy prompted many large businesses to shift their headquarters to Tokyo from cities such as Osaka (the historical commercial capital). Such moves allowed companies to take advantage of better access to government. However overcrowding and the high cost of living in Tokyo have slowed this trend in recent years. Tokyo remains one of the most expensive cities in the world.

The Tokyo Stock Exchange is second in size only to the New York Stock Exchange, and at the peak of the Japanese economic bubble in the early 1990’s it accounted for more than sixty percent of the stock market value of the whole world.

Tokyo only has about 8,000 hectares of farm land, concentrated in the west. The greater Tokyo area contains a large amount of forest, especially in the mountainous western regions. Tokyo’s lumber output is in decline however due to falling prices, increased production costs, and an aging population in the tree-farming areas. Tokyo Bay was once a major source of fish but today most of Tokyo's fish production comes from the outlying islands. Tourism in Tokyo also contributes to the local economy.