Pu'er tea is a fermented drink made from the leaves of the tea plant, Camellia sinensis. Two novel bacteria, designated strains b09i-3(T) and b13i-1, were isolated during the process of fermentation of this tea. These isolates were Gram-positive, endospore-forming, motile rods that grew at 25-42 degrees C and pH 5.5-10.4. The DNA G+C content was 56.6-58.4 mol%, the predominant isoprenoid quinone was MK-7 and the predominant cellular fatty acid was anteiso-C(15 : 0) (49.0-50 % of the total). Phylogenetic analysis based on 16S rRNA gene sequences showed that strains b09i-3(T) and b13i-1 shared 99.9 % similarity and were affiliated with a cluster within the family Paenibacillaceae. Strains b09i-3(T) and b13i-1 were related most closely to Paenibacillus ginsengihumi DCY16(T) (97 % 16S rRNA gene sequence similarity). Levels of DNA-DNA relatedness between the two novel isolates and P. ginsengihumi DCY16(T) were below 56 %. The phylogenetic and phenotypic characteristics of these novel isolates allowed them to be distinguished clearly from recognized species of the genus Paenibacillus. Based on these data, strains b09i-3(T) and b13i-1 are considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus pueri sp. nov. is proposed. The type species is b09i-3(T) (=KCTC 13223(T)=CECT 7360(T)).