The new arrivals are red pandas, distantly connected to the racoon family.
They were born at the Highland Wildlife Park, near Kingussie, Inverness-shire, to resident red pandas Kitty and Kevyn.
The pair produced the park's first ever red panda cub, Kush, last summer, but keepers were stunned with this year's double success.
The unnamed cubs, whose sexes remain unknown, were born blind on June 15, only opening their eyes after 18 days. Due to their sensitivity, the animals will remain off show for the next few weeks.
Douglas Richardson, Head of Living Collections for the Highland Wildlife Park, said: "We are of course thrilled by the birth of twin red pandas, but it is doubly satisfying as a number of red panda pairs in zoos breed once, then do nothing in subsequent years. The fact that Kitty has produced cubs two years in a row is a very strong indication that our enclosure, diet and husbandry regime suits this pair of pandas."
Kitty and Kevyn, who are both three years old, joined the Highland Wildlife Park in 2012 with Kitty arriving from Berlin Tierpark and Kevyn two months later from Aalborg Zoo, Denmark.
While red pandas are not related to giant pandas, like them they are highly endangered. Their natural habitats in the Himalayas are threatened by the destruction of the mountain forests.