In this paper, we consider the problem of generating, ranking, and unranking of AVL-trees with n leaves. We represent AVL-trees by integer- pair sequences, called LDP-sequences. Then we propose a linear ordering among these sequences, i.e., among the AVL-trees. The problem of ranking is to determine the oder number (rank) of a given tree in this ordering, unranking means constructing the tree of a given rank. The main result is that ranking and unranking can be done in O(n log\({}^ 2n)\) and O(n log\({}^ 3n)\) time, respectively, after a preprocessing step that takes \(O(n^ 2\log n)\) time.