A tepui /ˈtɛpwi/, or tepuy (Spanish: [teˈpuj]), is a table-top mountain or mesa found in South America, especially in Venezuela and western Guyana.

The word tepui means "house of the gods" in the native tongue of the Pemon, the indigenous people who inhabit the Gran Sabana.

Tepuis tend to be found as isolated entities rather than in connected ranges, which makes them the host of a unique array of endemic plant and animal species.

These table-top mountains are the remains of a large sandstone plateau that once covered the granite basement complex between the north border of the Amazon Basin and the Orinoco, between the Atlantic coast and the Rio Negro.

[4] There are 115 such mesas in the Gran Sabana in the south-east of Venezuela on the border with Guyana and Brazil, where the highest concentration of tepuis is found.

[6] Because of their great age, some tepuis exhibit surface features and caves typical of karst topography, formed in more water-soluble rocks such as limestone.

The tepuis are often referred to as the Galápagos Islands of the mainland, having a large number of unique plants and animals not found anywhere else in the world.

It has been hypothesized that endemics on tepuis represent relict fauna and flora that underwent vicariant speciation when the plateau became fragmented over geological time.