A collection of 21 root nodule bacteria were isolated from some woody legumes that belong to 8rngenera from various regions of Ethiopia. The isolates were presumptively tested to checkrncontaminations followed by morphological and physiological characterizations, and numericalrnanalysis of phenotypic data using a computer cluster analysis applying UPGMA (NT-SYS versionrn2.1). Isolates of Erythrina brucei and a species of Crotalaria, Indigofera and Tephrosia werernselected as representatives and cross-inoculated on Phaseolus vulgaris and Vigna unguiculata forrnauthentication and symbiotic effectiveness evaluation .The isolates showed a wide range ofrnmorphological and physiological characterstics. Most of the isolates were found to be slowrngrowing, NaCl and streptomycin sulfate sensitive but able to utilize a wide range of carbohydrates,rnand grow over a wider temperature and pH ranges. The analysis of phenotypic data revealed that atrna boundary level of 64.8% average similarity, all the isolates were grouped in to 3 clusters while atrn92.2% the isolates were further grouped in to 5 clusters except 8 isolates. All the four crossinoculatedrnrepresentative isolates elicited nodulation on Phaseolus vulgaris but one of them failedrnto nodulate Vigna unguiculata, which might be due to genetic incompatibility. An isolate ofrnCrotalaria species showed the highest symbiotic effectiveness with both Vigna unguiculata andrnPhaseolus vulgaris suggesting that the isolate is worthy of further field testing and of greatrnpotential application in improving the yield of these grain legumes.