Common bean (Phaseolus vulgaris L.), originated from Central and North America (Bitocchi et al., 2012), has been recognized and widely planted as a grain/vegetable legume in the world due to its high protein, low fat, and rich in various trace elements in terms of nutritional composition (Sgarbieri, 1989). It is a legume normally from root nodules as a symbiosis with some soil bacteria in the genus Rhizobium, but also with some strains from Bradyrhizobium, Pararhizobium, Sinorhizobium, Paraburkholderia and Cupriavidus in different regions (Lindström and Mousavi, 2020). Inside the nodules, these symbiotic bacteria are able to fix atmospheric nitrogen into ammonia for using by the host plants (Shamseldin and Velázquez, 2020). The genus Rhizobium was first proposed by Frank and affiliated in the family Rhizobiaceae within the order Rhizobiales, class Alphaproteobacteria (Ormeño-Orrillo et al., 2015). In the past decades, the taxonomy of genus Rhizobium has been developed rapidly, and both the taxonomic status and number of species of this genus have been continually modified and updated. At the time of writing, the genus Rhizobium comprises more than 90 species with validly published names (https://lpsn.dsmz.de/genus/rhizobium), including the recently described species Rhizobium acaciae (Hsouna et al., 2023), Rhizobium croatiense (Rajnovic et al., 2022), Rhizobium redzepovicii, Rhizobium rhododendri (Kuzmanović et al., 2023), Rhizobium setariae (Kang and Seo, 2022) and Rhizobium chutanense (Huo et al., 2019). All the members of Rhizobium are Gram-stain-negative, aerobic, non-spore-forming, motile, rod-shaped, and have high G + C contents of 57–66 mol% (Yang et al., 2022a). Chemotaxonomically, most members of Rhizobium possess Summed feature 8 (C18:1 ω7c and/or C18:1 ω6c) as the major fatty acids. During an investigation of rhizobia diversity in root nodules of Phaseolus vulgaris in Heilongjiang Province, two novel Rhizobium groups represented by strains BJ04T and MC63T were founded. In order to define their species affiliation, the representative strains of these two groups were further characterized in the present study and two novel species named as Rhizobium binxianense sp. nov. and Rhizobium mulingense sp. nov. were described here.