Falcaustra tintlwini sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Batagur trivittata (Testudines, Geoemydidae) is described and illustrated. Falcaustra tintlwini represents the 20th Oriental species assigned to the genus and is distinguished from other Oriental species by the distribution pattern of the caudal papillae (6 precloacal, 12 postcloacal, and 1 median), length of spicules (0.43–0.50 mm) and absence of a pseudosucker.