Three phosphate solubilizing bacteria coded as Jim41, GimlO and Hagl2 werernisolated from Jimma, Gimbi and Hageremariam soils, respectively. They wererncharacterized to generic level and found to belong to pseudomonas spp.rnTricalcium phosphate (TCP), rock phosphate (PR) and old bone (OB)rnsolubilization efficiency of these isolates and one reference commercialrnstrain (Psellndomon([s striata), introduced from India was studied in thernlaboratory at 5, 10, IS and 20 days of incubation. At the end of the specifiedrnincubation date, samples were taken and filtered to remove insolublernmaterial. The filtrate was then centrifuged and analysed for soluble P usingrncolorimeter. The result revealed that all PSB isolates solubilizedrnsignificantly (P~O.Ol) greater amount of tricalcium phosphate and rockrnphosphate over the un inoculated control. The highest amount ofrnsolubilization was achieved with Jim41 followed by GimlO, Hag12 andrnPseudomonas striat([ in that order. Isolate GimlO, Hag12 and P. striatarnsolubilized significantly (P:'O. 0.01) greater amount of old bone than therncontrol and isolate Jim41. This suggests that isolate Jim41 cannot be used asrnPSB inoculant where old bone is required as insoluble p fertilizer.rnGreenhouse pot experiments with regard to the effect of inoculation of PSBrnisolates on the growth of faba bean were conducted. The treatments includedrntwo PSB isolates coded as Jim41 and GimlO, and two P-sources (rockrnphosphate and triple super phosphate) in various combinations, with andrnwithout Rhizobium. The result showed that following inoculation, the twornPSB inoculants established well in the rhizosphere of faba bean andrndisplayed the highest population during i h week. Inoculation of PSBrnisolates along with the application of rock phosphate significantly (P:'O. 0.01)rnimproved the dry matter yield of faba bean compared to the control with andrnwithout inoculation of RhizobiulIl. Isolate Jim41 and GimlO inoculated with rock phosp ha te were found to increase the dry matter yield of faba bean byrn34 and 39% over the uninoculated control without inoculation of Rhizobium,rnand by 33 and 31 % with the inoculation of Rhizobium respectively. The dryrnmatter yield increment obtained from inoculation of both PSB isolates alongrnwith PR was comparable to that obtained with the application of triple superrnphosphate (TSP). This implies that there may be a possibility to use the lessrnexpensive PR together with PSB than the more expensive TSP. Analysis ofrnplant tissue P content revealed that the PSB inoculants improved the Puptakernof faba bean where PR was applied as p-sources. Inoculation of PSBrnhas also improved the nitrogen accumulation of faba bean. In the light of thernpresent finding many of the conclusions are subject to verification. Thus,rnfuture research directions are discussed.