Two new species of free-living marine nematodes of the genus Wieseria are described from the sublittoral sediment of the Jiaozhou Bay in Qingdao. Wieseria sinica sp. nov. is characterized by having short labial and cephalic setae in a backward direction; oblong amphidial foveas with double contour; arcuate spicules with alea; ring-like guberculum; and clavated tail. Wieseria tenuisa sp. nov. is characterized by its very large “a” value (133.6), long labial setae in a forward direction; spicules with alea and hooked proximal end; rodlike gubernaculums; and relatively longer clavated tail (7.9 a.b.d. long). It differs from Wieseria sinica sp. nov. mainly by the longer labial setae, slightly straight spicules with hooked proximal end, and its thinner body. Amended dichotomous key to male species of Wieseria is provided.