Illustrated descriptions of two new species of free-living nematodes found in the dense mangrove thicket in river estuaries of Vietnam are given. Metachromadora (Metachromadoroides) orientalis sp. n. is morphologically similar to M. (M.) zaixsi Pastor de Ward, 2004, but it has longer and thicker tail, a more anterior position of the vulva, a different shape of amphidial foveae, a larger pharyngeal basal bulb, and longer spicules, and males have differently armed tails. Morphologically, Terschellingia lutosa sp. n. is closer to T. elegans Gagarin, Nguyen Vu Thanh, 2003 and T. supplementata Tchesunov, 1978 and differs from both of them by a less slender tail, a wider body at the area of head setae, and longer spicules. An identification key to the valid species of the genus Metachromadora (Metachromadoroides) is given.