A new cestode, Macrobothridium sinensis n. sp., is described from the spiral intestine of Platyrhina sinensis from coast of Xiamen, China. It is the first record of the order Diphyllidea in China. The new species can be distinguished from the 3 previously described species of Macrobothridium by the testes number (16–24 vs. 29–37, 27–46, and 5–6, in M. rhynchobati, M. euterpes, and M. syrtensis, respectively) and a single-row arrangement of testes; M. sinensis is most similar to M. euterpes in strobila length (1.77–6.23 vs. 2–4.5 mm) and number of segments (6–8 vs. 5–9). In addition, M. sinensis differs from M. rhynchobati and M. syrtensis in the strobila length, ovary shape, and number of apical hooks. The uterine pore is the first described in the Diphyllidea; thus, the present uterine pore can now be used to distinguish Macrobothridium from Echinobothrium and Ditrachybothridium in the Diphyllidae.