A bacterial strain WN9, which produced a new type of extracellular polysaccharide, was isolated from soil samples. By morphological, physiological, biochemical, and phylogenetic studies, strain WN9 was identified as a Paenibacillus sp. and it was named as Paenibacillus sp. WN9, which produced a high molecular extracellular polysaccharide from glucose. The molecular weight of the exopolysaccharide (EPS-WN9) was estimated to be about 31.5 mega-Da. The FT-IR spectrum of EPS-WN9 revealed typical characteristics of polysaccharides. EPS- WN9 consisted of D-glucose and D-mannose with a molar ratio of 1:1.4 being identified as a neutral sugar component. The acidic component of EPS- WN9 was tyrosine. Rheological analysis of EPS- WN9 revealed that the pseudoplastic property and its apparent viscosity remained stable at various temperatures and pHs.