In this paper, a necessary and sufficient condition for the existence of an efficient 2-dominating set in a class of circulant graphs has been obtained and for those circulant graphs, an upper bound for the 2domination number is also obtained. For the circulant graphs Cir(n, A), where A = {1, 2,. .. , x, n − 1, n − 2,. .. , n − x} and x ≤ n−1 2 , the perfect 2-tuple total domination number γ ×2t has been studied. Also some 2-tuple total dominating 2-excellent circulant graphs and 2-tuple total dominating 2-restricted circulant graphs are identified. It is proved that any subgroup of the finite cyclic group Z n can be a perfect 2-tuple total dominating set of Cir(n, A) for some generating set A.