The present study was mainly focused on engineering geological characterization, assessmentrnand the suitability analysis of the substructures of the Addis Ababa LRT alignment and to evolvernpossible engineering concerns or outlooks for the likely engineering geological gaps along thernproposed alignment. For this field observation, investigation, sampling and laboratory tests forrnphysical and strength properties assessment were performed on representative samples from subgradernembankment material (Yerer-2 subgrade) and ballast stone materials (Galan Quarry). In allrnLRT project there is no subballast proposed and used by the contractor (CREC). Because insteadrnof subballast, 5cm thick asphalt concrete is proposed in design specification of the LRT project.rnFurther, attempts were also made to identify and characterize the topographic classifications andrnsurface drainage setup of the area by reviewing the relevant literatures and by using the elevationrnmap of the study area. Based on the laboratory test Soil Classification such as; Grain sizerndistribution and Atterberg Limits, Strength tests (California Bearing Ratio (CBR)), Moisture/rnDensity Relationship (modified proctor tests), and direct shear characterization, the sub-gradernwas found to be suitable. In addition to this it has been assessed that most of the identifiedrnsubgrade fill material is granular in nature. Based on the index properties, with its AASHTOrnclassification is A-1-a (0), A-1-b (0) and [GW, GP] USCS classification systems. Pertaining tornits consistency limits, the subgrade material falls below A-line in the Cassagrade plasticity chartrnindicating that moderately plastic silt to low plastic. The bearing capacity of the subgradernmaterial is above (ERA, 2002) specifications.rnIn laboratory gradation, specific gravity, water absorption, impact value, crushing value, abrasionrnresistance, soundness, Slake durability test and peterographic analysis were done for the ballastrnstone accordingly. Pertaining to the recommended standards and specifications set for ballastrnaggregate, all the engineering suitability results indicate that the studied material is suitable forrnintended use except for its water absorption values (which is above permissible) AREMA,rn(2010), and higher content in plagioclase feldspars which makes an aggregate more sensitive tornweathering.