Many researchers have done researches on unsaturated soil mechanics worldwide to bring thernunsaturated soil mechanics in to practices. Among those researches some of them focused onrnsimplifying the complex and expensive testing mechanism by developing models which can bernused to predict the unsaturated soil parameters from basic soil prosperities such as Grain SizernDistribution (GSD) and Plasticity Index (PI) along with the saturated shear strength parameters.rnSoil water characteristic curve (SWCC) was proved to have good relationship with thernunsaturated soil parameters. In this study an attempt was made to check whether those developedrnmodels would work for expansive and red clay soils found in Addis Ababa.rnUsing the model developed by Fredlund and Xing (1994) along with the correlation equationrngiven by Perera et.al (2005), family of SWCC for soils found in Addis Ababa has been plotted. Itrnwas observed that the family of SWCC plotted was out of the widely referenced family of curvesrndeveloped by Zapata et.al (2000) to some extent. Even though the family of curves seems to bernout of the range provided by Zapata et.al (2000), the model gave good prediction for thernunsaturated shear strength parameter Î¦b.rnThe percentage error between the measured values of unsaturated shear strength parameter Î¦b inrnprevious researches of Habtom (2010) and Getaneh (2010) with predicted unsaturated shearrnstrength parameter Î¦b in this study was compared.rnFor red clay samples the percentage error lie in the range 2.07 to 6.37% for suction ranges ofrn36.67 to 52.9 kPa and at lower suctions of 16.75 and 21.5 kPa the percentage error ranges fromrn11.42 to 25.39% .rnFor expansive soil samples for suction of 23.1 and 32.9 kPa, the percentage error is in the rangernfrom 3.86 to 6.13%. For suction values of 14.5 and 52 kPa the range of error is about 9.45 torn13.40% and for suctions of 38.8 and 48.6 kPa the error lies between 18.94 and 38.84%.