A road is very important for the community, because it is base for the socio-economic interactionrnamong people. Based on road life and its economic considerations, road pavement designsrnmainly need good sub-grade materials or reinforcement of existing problematic soil. Naturalrnfibers have capability to reinforce problematic soils such ranging from clay to silty sand.rnWolaita (project area) is one of the highly populated area in Ethiopia and its land is almostrncompletely covered by farm and house. The soil in wolaita area is lateritic clay. However, roadrnconstruction siteâ€™s soil does not fulfill the sub-grade soil requirements economically. Hencernhundreds of millions metric cube soil is needed for sub-grade layer and the same volume of soilrnis cut to drop site in one road project. This research work come up with mechanism, mechanicalrnconjugation of random distributed local natural fibers and soil, in order to reinforce thernproblematic sub-grade soil.rnIn general the research work comprises the tasks such as characterization and selection ofrnfibers, representative problematic soils and soil-fiber mixtures. Method of characterization isrndone as per AASHTO and ASTM test methods which are recommended in Ethiopian RoadrnAuthority. Accordingly the characterization of the worst problematic soil and selected fibersrn(Enset ventricosum and Teff straw fibers) is done before conjugating them. The effect of fibersrnpercentage by weight and of fiber length in the soil on CBR, surcharged swell, dry density,rnmoisture content and their optimum improvements are discussed in this paper. The percentage ofrnindividual fiber in the soil is taken as 0%, 0.25%, 0.5%, 0.75%, 1%, and 1.25% by air dryrnweight. The result show that MDD is decreased and OMC is increased with increased fibersrnpercent while CBR value is increased until 1% for Enset fiber and 0.75% for Teff straw fiberrnwith fiber length of 6 cm. However, the degree of improvement of fiber mixed soil is 157 and 133rntimes greater than the soil without the fiber respectively. One point unsoaked CBR test showsrnthat the value increased from 57% to 62%. 4.54kg surcharged swell value of teff straw fiberrnconjugated soil is decreased from 5 to 3 as percent of fiber increased from 0% to 0.75%,rnrespectively and decreased from 5 to 3.5 as fiber increased from 0% to 1% respectively for Ensetrnfiber. According to improvement, change in road pavement design as per ERA manual and itsrnsubsequent benefits are also discussed in this paper. Finally, appropriate recommendations arernwritten according to the finding.