Bursaphelenchus parvispicularis n. sp. is described and figured. The new species was isolated from the bark of a dead oak tree, Quercus mongolica var. grosseserrata, and reared on Botrytis cinerea. Specimens were collected from a 2-week-old culture on Botrytis cinerea. The new species has a body length of 894 (711-1012) μm in the female and 764 (600-870) μm in the male, a ratio of 33.4 (29.7-37.1) in the female and 35.6 (31.4-45.3) in the male, and c and c′ ratios of 16.7 (14.8-19.0) and 4.4 (3.9-5.1), respectively, in the female and 24.3 (20.0-28.4) and 2.5 (2.2-2.8), respectively, in the male. The stylet is 14-16 μm long in the female and 13-15 μm in the male; there are three lines in the lateral field; the spicules are small (13 (13-15) μm long) and broad; there are seven (2 + 1 + 2 + 2) male caudal papillae; the 'bursa' varies from roundish trapezoid to rectangular with a concave terminus, and the female tail is tapered with clearly annulated dorsal surface near the tail tip and a rounded terminus. Based upon morphology the new species belongs to the B. hofmanni-group sensu Braasch. However, the new species is distinguished from the other B. hofmanni-group species by the size and form of the spicule, female tail shape, and morphometric values. Based on the molecular phylogenetic analysis of the DNA base sequences of ribosomal DNA and mtCOI gene, the new species was close to two B. hofmanni-group species (B. paracorneolus and B. hofmanni) and to B. hylobianum. This result is in accordance with their morphological similarity.