The larvae of the mangrove sesarmid crab Neosarmatium trispinosum Davie, 1994, were reared in the laboratory. Five zoeal stages and one megalopa are described in detail and illustrated. Morphologically, the zoea larvae of N. trispinosum are similar to those of other species of Neosarmatium in that they share most of the following characters: no lateral carapace spines; 1 5, 5, and 0 1 6 setae on the endopods of the maxillule, the maxilla, and the second maxilliped, respectively; uniform setal formula on the basis of the first (2,2,3,3) and the second (1,1,1,1) maxilliped. The differences between the zoeae and the megalopae of N. trispinosum and those of its congeners are discussed briefly.