sup>—Road construction in Ethiopia is booming and radiating from Addis Ababa towards North-East and East-West directions to fulfil its long term development program. Transportation is a prime mover to all sectors in the country to uplift the economic activities of the populace in the locality. In most countries, experience and related literatures have revealed that road construction labor costs accounted at 30-60% of the total c ost of a project, depending on the terrain and s ource of materials, labor and equi pment to be utilized. Therefore, construction labor productivity plays a vital role to the performance and profitability of road construction projects.Road sector construction projects in Ethiopia are means through which development strategies are achieved. This research study gives insight on the assessment of the factors affecting labor productivity in road construction projects through a structured questionnaire survey of 83 respondents working on construction road projects in Oromia Region, Bale Zone. Respondents were required to rate how the 61 factors affecting labor productivity with respect to the importance and frequency of occurrence. Understanding these factors is helpful for the construction professionals who work on the initial phase of construction planning in order to efficiently deliver the project plan and to solve poor labor productivity. The results of this survey were then analyzed using the Relative Importance Index (RII) and ranked. The reliability of these 61 factors for assessing the effect on labor productivity were tested by Chronbach’s alpha measurement, and the results indicated that the 30 factors tes ted are r eliable (α= 0.973), and checked by S PSS. Result of this a nalysis s howed that there ar e 11 gr oups w hich have significant impacts on the labor productivity ranked as Material and Equipment Factor with RII=0.819, Manpower and Work Force Factor with RII=0.764, Management Factor with RII=0.737, Quality Factors with RII=0.720, Supervision Factor with RII=0.699, Safety Factor with RII=0.691, Motivation Factor with RII=0.682, Schedule Factor with RII=0.647, Political Factor with RII=0.620, Natural and environmental Factor with RII=0.566 and Cultural and Religious Factor with RII=0.541. Based on the results of this research study, the top factors that affect labor productivity includes: Lack of experience of labor, M aterial construction shortage, Lack of labour skills, Accident, Tools and Equipment shortage, Labor’s bad habit, Poor site management, Lack of Labor surveillance, Payment delay and Ignore safety precautions. Therefore, this research study suggests that the contractors should assign project managers and construction supervisors with sufficient managerial s kills in r oad c onstruction pr ojects so that w hen the re ar e an y pr oblems which may arise, i t would be acted and solved immediately at the project site. On the other hand, the role of the Ethiopian government in project implementation is very significant, which requires proper attention to the productivity issue to enforce hard and fast laws and regulation which help to obtain productive work force in the road construction industry. Index Terms—Contractors, Economic and social dev elopment, Factors affecting l abor pr oductivity, Government r ole, M anagerial skills, Road construction, Road sector in Ethiopia.