Ten strains of Rhizobium leguminoserum (bv. Phaseoli) were evaluated to asses the N-fixing ability in an acid inceptisol in terms of N-assimilation, N-uptake and relative effectiveness as compared to fertilizer N. Strains SSF48, SSF55, SSF72 and SSF73 have been found promising for French bean in acid inceptisolof temperate region. These were also superior to 40 kg N/ha to have better nodulation, plant dry matter and grain yield and at per with respect to N-assimilation and uptake by plants. Highest grain yield of 18.4 q/ha and N-uptake (2.293g/pl) was recorded with the strain SSF69 followed by SSF73. Relative effectiveness of strain as compared to 40 kg N/ha was also recorded highest with same strains. N-assimilation, uptake plant dry matter and grain yield were significantly and positively correlated with nodulation indicating synergistic effect of inoculation. The relative effectiveness of the strains followed the order as: SSF69 > SSF73 > SSF70 > SSF50 > SSF72 > SSF55.