The construction industry in developing countries like Ethiopia is booming at a faster growth rate due to an ever-increasing population and urbanization. The industry uses concrete as the main input. Thus, it increases the demand for aggregates which constitutes around 60 to 75% of concrete volume. Eucalyptus Kernel (EK) is a natural forest waste from Eucalyptus tree fruit drops. The fruits are irregular in shapes and variable in size but all cone shaped. The main aim of the study was using Eucalyptus Kernel as partial replacement of coarse aggregate to produce lightweight concrete by assessing the physical properties of kernel by checking its water absorption, moisture content, specific gravity, gradation, bulk density, soundness, flakiness index, elongation index and chemical properties. The other use of Eucalyptus Kernel as partial replacement of coarse aggregate in concrete has the benefits in the aspects of cost and reduction of structural self-weight. A mix of C – 25 concrete was prepared with 0%, 10%, 20%, 30% and 50% replacement of coarse aggregate by Eucalyptus Kernel aggregate. Five series of mixes for 45 cubes and 24 beams were prepared and the suitability of produced concrete was checked using slump, water absorption, shear strength, and compressive strength tests. Here the 0% replacement concrete was used as a control or reference mix. The percentage of Eucalyptus Kernel coarse aggregate increases the water absorption capacity of test cubes. The compressive strength of concrete was tested on the 7th, 14th, and 28th days, and the results show that as the replacement ratio of Eucalyptus Kernel aggregate increases the compressive strength of concrete decreases. Even then, it is possible to replace up to 10% for the production of C -25concrete. The shear strength of concrete was tested on the 7th and 28th days, and the results show that as the replacement ratio of Eucalyptus Kernel aggregate increases, the shear strength of concrete decreases. However, it is possible to replace up to 10%. The outcome indicates that the compressive strength of the optimum mix design was 26.28MPa and the shear strength of the optimum mix design was 58.4kN which is an average failure load capacity for 28 days curing. When a small amount of Eucalyptus Kernel is mixed with concrete, it forms a bond by up to 10 percent. Key Words: Coarse aggregate, Compressive strength, EK, Lightweight concrete, Workability