The Mumbai Marathon is an annual international road running competition over the marathon distance that is held in Mumbai, India, each January. The course records set in 2011 were also the fastest times ever run for the marathon on Indian soil – 2:09:54 by Girma Assefa and 2:26:56 by the women's winner Koren Jelila Yal. The day's events also include a half marathon race which is contested by the top-level Indian runners.

First held in 2004, the Mumbai Marathon was part of "The Greatest Race on Earth", an event sponsored by Standard Chartered Bank. The other three legs of this four-marathon race were the Singapore Marathon, the Nairobi Marathon and the Hong Kong Marathon. The race became an IAAF Silver Label Road Race in 2009 and an IAAF Gold Label Road Race in 2011.

The prize money for the fastest runners in men's and women's category are $31,000 each, with an additional $2,250 being awarded to the fastest Indian citizen (men and women) in the full and half marathon categories. The race has five separate race categories: Marathon (42.195 km), Half Marathon (21.097 km), Dream Run (7 km), Senior Citizens' Run (4.3 km) and Wheelchair (2.5 km).

Mumbai /mʊmˈbaɪ/, also known as Bombay /bɒmˈbeɪ/, is the capital of the Indian state of Maharashtra. It is the most populous city in India, and the fourth most populous city in the world, with a total metropolitan area population of approximately 20.5 million. Along with the neighbouring urban areas, including the cities of Navi Mumbai and Thane, it is one of the most populous urban regions in the world. Mumbai lies on the west coast of India and has a deep natural harbour. In 2009, Mumbai was named an Alpha world city. Mumbai is also the richest city in India, and has the highest GDP of any city in South, West or Central Asia.

The seven islands that came to constitute Mumbai were home to communities of fishing colonies. For centuries, the islands were under the control of successive indigenous empires before being ceded to the Portuguese and subsequently to the British East India Company. During the mid-18th century, Mumbai was reshaped by the Hornby Vellard project, which undertook the reclamation of the area between the seven constituent islands from the sea. Completed by 1845, the project along with construction of major roads and railways transformed Bombay into a major seaport on the Arabian Sea. Economic and educational development characterised the city during the 19th century. It became a strong base for the Indian independence movement during the early 20th century. When India became independent in 1947, the city was incorporated into Bombay State. In 1960, following the Samyukta Maharashtra movement, a new state of Maharashtra was created with Bombay as capital. The city was renamed Mumbai in 1996.