A Gram-positive， spore-forming， rod-shaped and motile bacterium， designated strain 1-25(T)， was isolated from the rhizosphere of Quercus aliena var. acuteserrata in Taibai Mountain， Shaanxi Province， China. 16S rRNA gene sequence analysis showed that strain 1-25(T) belongs to the genus Paenibacillus. Strain 1-25(T) was found to be closely related to Paenibacillus harenae and Paenibacillus castaneae with 96.0 and 95.9 % 16S rRNA gene sequence similarities， respectively. The strain was observed to grow optimally at 28 °C and pH 7.5. The major isoprenoid quinone was found to be menaquinone-7. The dominant cellular fatty acids were identified as anteiso-C15:0 and iso-C15:0. The diagnostic diamino acid in the cell-wall peptidoglycan was found to be meso-diaminopimelic acid. The DNA G+C content was determined to be 41.6 mol%. On the basis of phenotypic characteristics and molecular properties， strain 1-25(T) is considered to represent a novel species of the genus Paenibacillus， for which the name Paenibacillus quercus sp. nov. is proposed. The type strain is 1-25(T) (=CCTCC AB2013265(T) = KCTC 33194(T)).