Strain S22(T), a novel cellulolytic bacterium was isolated from the rhizosphere of pine trees. This isolate was Gram-reaction positive, motile and rods, and formed terminal or subterminal ellipsoidal spores. S22(T) represented positive activity for catalase, oxidase, esterase (C4), esterase lipase (C8), beta-galactosidase, leucine arylamidase, and hydrolysis of esculin. It contained meso-diaminopimelic acid as the diagnostic dia-mino acid in the cell-wall. The predominant isoprenoid quinone was menaquinone 7 (MK-7), and the major cellular fatty acids were anteiso-C(15:0) (52.9%), iso-Ci(16:0) (11.3%), and iso-C(15:0) (10.0%). The DNA G+C content was 43.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that this isolate belonged to the family Paenibacillaceae. S22(T) exhibited less than 97.0% 16S rRNA gene similarity with all relative type strains in the genus Paenibacillus, and the most closely related strains were Paenibacillus anaericanus MH21(T) and Paenibacillus ginsengisoli Gsoil 1638(T), with equal similarities of 95.8%. This polyphasic evidence suggested that strain S22(T) should be considered a novel species in the genus Paenibacillus, for which the name, Paenibacillus pini sp. nov., is proposed. The type strain is S22(T) (=KCTC 13694(T) =KACC 14198(T) =JCM 16418(T)).