Subgrade soil characterization in flexible pavement design isnecessary for estimating the structural capacity of flexible pavementsand then determining tbe pavement layer thicknesses. Several non-linearand linear models have been used to characterize the subgradesoils. The current bulk and deviatoric stress models have limitedapplications since they are essentially developed for a particularsoil type. Few other models are restricted by the multiple collinearityproblems in the regression analysis. A regression model with confiningand deviatoric stresses as attributes is adopted in this paperto analyze the repeated load triaxial test results. This modelis simple, easy to analyze the repeated load triaixial test resultsand does not have any structural type collinearity problems. Thispaper presents the regression model analysis results on differentsubgrade soils including mixed soil types. The repeated load triaxialtests conducted on granular, cohesive and mixed soil types atvarious moisture content levels are first analyzed to determinethe model constants. The model constants are then correlated withthe basic soil properties. The correlations are evaluated in theirreliability in predicting the resilient properties of the samesubgrade soils. This evaluation, which is fairly successful, showedthat this approach can be used to predict the resilient propertiesof similar type soils. This approach will save significant projectcosts since core sampling and resilient modulus testing taskscan be averted.