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Mango belongs to the genus Mangifera in the family Anacardiaceae (Sapindales). According to Kostermans and Bompard (1993), the genus Mangifera contains c.69 species. The centre of diversity for the Mangifera is tropical and subtropical Asia from the equator to 27°N latitude. The Malay Peninsula, Borneo and Sumatra, which comprise western Malesia, contain the highest species diversity. Most of the species in the genus are canopy and emergent trees (30–40 m height) of the tropical lowland rainforests. None the less, a few species are found above 1500 m, i.e. M. bompardii, M. dongnaiensis and M. orophila. Mangifera austro-yunnanensis, M. indica, M. persiciformis and M. sylvatica have natural ranges that can extend north of the Tropic of Cancer. Wild mangoes generally are distributed at very low densities on well-drained soils. The trees are evergreen, and flowering is irregular so that fruiting at 2–8 year intervals is typical. Although interspecific hybridization studies have been limited, there appear to be incompatibility barriers that separate many of the species.

The Mangifera genus has been subdivided into two subgenera on the basis of morphological characters (Kostermans and Bompard, 1993): Limus (Marchand) Kosterm and Mangifera. Species within subgenus Limus are remotely related to mango and appear to be more primitive than species in subgenus Mangifera. The Limus species are found in the tropical rainforest of western Malesia, with the exception of M. foetida, which also is found in New Guinea, and M. odorata, which no longer exists in the wild and is known only in cultivation. Mangifera caesia, M. foetida, M. kemanga and M. odorata are all widely grown for their fruit in the humid tropics of South-east Asia. Mangifera pajang is cultivated on a limited scale in Bali (Bompard and Schnell, 1998).

There are 47 Mangifera species within subgenus Mangifera, which has been subdivided into five sections: Marchandora Pierre, Euantherae Pierre, Rawa Kosterm, Mangifera Ding Hou and a group of species of uncertain position. Section Marchandora has only a single species, M. gedebe, which grows in areas subject to periodic flooding. The Euantherae has three species, M. caloneura, M. cochinchinensis and M. pentandra, which occur in Thailand, Myanmar, Indochina and northern Malaysia in the transition zone between the humid tropics and the drier monsoon climate. All of these species are cultivated for their fruit. Section Rawa is not well delimited and contains nine species, of which only M. griffithii and M. microphylla are cultivated. The species within section Rawa generally grow in lowland wetlands in west Malesia.

The common mango is one of 30 species in section Mangifera. This section has been further divided into three sections on the basis of floral structure: (i) pentamerous flowers; (ii) tetramerous flowers; and (iii) an intermediate group. The pentamerous group contains 14 species, including M. laurina, M. minor and M. sylvatica, whose fruit bear similarities with the common mango. Mangifera laurina, which is highly resistant to anthracnose, is widely cultivated in the humid tropical lowlands. Mangifera minor occurs in east Malesia and grows in dry savannahs and tropical rainforests. Mangifera sylvatica occurs at the northernmost range of the genus in northern Myanmar, Thailand and Yunnan, China. There are 15 species with tetramerous flowers, of which M. altissima, M. torquenda, M. magnifica and M. quadrifida are grown for their fruit. The common mango and M. casturi, also cultivated for its fruit, are classified within the section having tetramerous and pentamerous flowers.

It is probable that the common mango was domesticated independently in different regions of Asia (Bompard and Schnell, 1998), thereby accounting for the two different ecogeographic races of mango that are recognized today: the monoembryonic, subtropical Indian and the Southeast Asian, tropical polyembryonic races. Mangifera indica is a heterogeneous, outcrossing species with a juvenile period that is c.7 years in length. The mango terminal inflorescence is a composed thyrsoid with both hermaphrodite and male flowers. The number of flowers and the ratio of hermaphrodite to male flowers varies depending on cultivar, climatic conditions, location on the tree and the level of tree productivity. Mukherjee (1950) considered that mango is an allotetraploid with 2n = 4x = 40; however, Duval et al. (2005), Schnell et al. (2005, 2006) and Viruel et al. (2005) have affirmed that M. indica is diploid using microsatellite markers.