A Gram-negative, rod-shaped and motile bacterial isolate, designated strain NS9(T), isolated from air of the Sainsbury Centre for Visual Arts in Norwich, UK, was subjected to a polyphasic taxonomic study including phylogenetic analyses based on partial 16S rRNA, gyrB and lepA gene sequences and phenotypic characterization. The 16S rRNA gene sequence of NS9(T) identified Massilia haematophila CCUG 38318(T), M. niastensis 5516S-1(T) (both 97.7% similarity), M. aerilata 5516S-11(T) (97.4%) and M. tieshanensis TS3(T) (97.4%) as the next closest relatives. In partial gyrB and lepA sequences, NS9(T) shared the highest similarities with M. haematophila CCUG 38318(T) (94.5%) and M. aerilata 5516-11(T) (94.3%), respectively. These sequence data demonstrate the affiliation of NS9(T) to the genus Massilia. The detection of the predominant ubiquinone Q-8, a polar lipid profile consisting of the major compounds diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol and a polyamine pattern containing 2-hydroxyputrescine and putrescine were in agreement with the assignment of strain NS9(T) to the genus Massilia. Major fatty acids were summed feature 3 (C16:1�s7c and/or iso-C15 : 0 2-OH), C16:0, C18: 1�s7c and C10:0 3-OH. Dissimilarities in partial lepA and gyrB gene sequences as well as results from DNA-DNA hybridizations demonstrate that strain NS9(T) is a representative of an as-yet undescribed species of the genus Massilia that is also distinguished from its close relatives based on physiological and biochemical traits. Hence, we describe a novel species, for which we propose the name Massilia norwichensis sp. nov., with the type strain NS9(T) (= CCUG 65457(T) =LMG 28164(T)).