Two new free-living marine nematode species of genus Tripyloides were discovered in intertidal sediments along Rudong coast of the Yellow Sea and on Qi′ao Island of the South China Sea, respectively. They are described here as Tripyloides conicus sp. nov. and Tripyloides boucheri sp. nov. T. conicus sp. nov. is characterized by outer labial setae two-segments, amphideal fovea circular, buccal cavity with four chambers and with a distinct tooth at the bottom, spicules slender and straight, gubernaculum kidney-like with two lateral denticles at distal end, tail sexual dimorphism (elongated conical in males, conico-cylindrical in females). T. boucheri sp. nov. is characterized by body size small, outer labial setae stout, two-segments, amphidial fovea small, circular, narrow conical buccal cavity without distinct tooth, male with papilliform precloacal supplements, spicules slender, gubernaculum with two lateral denticles at distal end, tail conico-cylindrical and not swollen terminally. An updated dichotomous key for fifteen species of the genus is also given.