Physalopteroides grismeri n. sp. (Spirurida, Physalopteridae) from the stomach of Emoia atrocostata (Squamata: Scincidae) collected in Peninsular Malaysia is described and illustrated. Physalopteroides grismeri n. sp. is the twentieth species assigned to the genus, the sixth from the Oriental region, and the first from Peninsular Malaysia. The new species is most similar to those species possessing symmetrical caudal alae, i.e., Physalopteroides agamae, Physalopteroides bahamensis, Physalopteroides dactyluris, Physalopteroides dryophisi, Physalopteroides geckonis, Physalopteroides grayiacola, Physalopteroides impar, Physalopteroides milneae, Physalopteroides minor, Physalopteroides quadridentatum, Physalopteroides tarentolae, Physalopteroides valdesi, Physalopteroides venancioi, and Physalopteroides versicoloris. Physalopteroides valdesi possesses 6 postcloacal papillae; P. dryophisi possesses 6–8 postcloacal papillae; P. grayiacola, P. geckonis, P. bahamensis, P. venancioi possess 8 postcloacal papillae; P. impar, P. minor, P quadridentatum possess 10 postcloacal papillae; P. milneae, P. agamae, P. dactyluris, P. versicoloris possess 12 postcloacal papillae; P. tarentolae and P. grismeri n. sp. possess 14 postcloacal papillae; however, spicules are absent in P. tarentolae, present in P. grismeri n. sp.