The Gran Canaria giant rat (Canariomys tamarani) is an extinct species of rat endemic to the island of Gran Canaria (Canary Islands, Spain).

This rodent is known from Holocene to pre-Hispanic fossil remains found at several places on the island of Gran Canaria, the youngest of which have been dated to shortly before the beginning of the Common Era.

[citation needed] The giant rat was herbivorous and terrestrial, with some digging skills and the ability to climb trees.

[2] The giant rat had an estimated typical head-and-body length of 28.7 cm (11.3 in) and tail length of 20 cm (7.9 in);[2] its average body weight is believed to have been in the 0.75–1.35 kg (26–48 oz) range.

It is believed that the arrival of humans and the introduction of feral dogs led to the extinction of both species.