The fauna of Madagascar is a part of the wildlife of Madagascar.

Madagascar has been an isolated island for about 70 million years, breaking away from Africa around 165 million years ago, then from India nearly 100 million years later. This isolation led to the development of a unique endemic fauna.

Before humans arrived about 2,000 years ago there were many large and unusual animals living there, descended from species that were originally present when Madagascar became an island, or from species that later crossed the sea to Madagascar. Ecological niches were often filled by animals with quite different histories from those on the African mainland, often leading to convergent evolution. A large proportion of these endemic Malagasy animals have died out since the arrival of humans, most particularly the megafauna.

Despite this, and massive deforestation, Madagascar is still home to an incredible array of wildlife, the vast majority of which is unique in the world. Madagascar is a primary spot for ecotourism, with more than fifty national parks and other protected reserves.

There are believed to have been only five colonization events of terrestrial mammals from mainland Africa. They are the tenrecs, the lemurs, the Malagasy carnivorans, the nesomyine rodents, and the now-extinct bibymalagasians. The other mammalian colonizations are the amphibious hippopotamuses (now extinct) and bats.