Effect of Testing Treatments on Compaction and Strength (CBR) Characteristics of Tropical Soils of Northwestern Ethiopia for Highway Subgrade Material Requirements Properties of tropically weathered residual soils are highly dependent on properties and features of parent materials from which they derived, though its influence reduces as the extent and period of weathering increases. Whereas as degree of weathering and erosion determined by climate, topography, vegetation and time. Various testing and pretesting treatments such as degree of drying and mixing, amount of applied energy and chemicals, moisture equilibration and stress relief period are used on samples collected from thirteen Test pits located along Aykel-Zufan-Angereb road. Which is located in Northwestern part of Ethiopia in a favorable climatic condition, topographic features and geological seating for intense tropical weathering. Based on the observed significant to nominal effects on consistency limits, gradation, moisture content, specific gravity, compaction and California bearing ratio characteristics of Aykel-Zufan-Angereb road subgrade soil, Sample preparation and testing treatments that gives meaningful and reputable test result are identified. Generally, sample preparation and laboratory testing treatments should have to simulate actual site condition in which test results applied on and evaluate. Compaction characteristics of coarser soils with a total finesse not more than 25% prominently depend on moisture equilibration period than grain breakage and pretest drying. But, specific gravity of these soils significantly influenced by pretest drying. On the other hand relatively finer soils with natural moisture content above 24% and finesse more than 40%, compaction characteristics significantly affected by both grain breakage and pretest drying. And also, liquid limit significantly influenced by drying and soil structure breakdown. These soils generally have significant molecular water removable by drying at high temperature that could alter soil characteristics. Most samples fulfill strength requirements satisfactorily, but fails to meet satisfy consistency limit and also particle size distribution to some extent. However consistency limits result evaluation in accordance to conventional specification understood as low strength and high volume change or high accumulation of unwonted clay minerals. But tests conducted in evaluating strength and volume change implicate the opposite to the predictions inferred from consistency limit results. This misconception testified by CBR test result that ranges from 10% to 48% with an average of 20%. CBR swell, free swell and clay activity confirms volume change not likely to occur. Therefore, the use of this locally available tropically weathered residual soil as a subgrade material is sound technical and also practically examined in western Ethiopia and tropical countries like Angola, Botswana, Kenya, and Brazil.