Clay is ground easily changeable consistency, when dry will be hard, if wet will be soft plastic, berkohesif and have fireworks shrinkage rapid influence of moisture content, therefore the need for soil stabilization for the sake of inability of the soil to maintain consistency and load bearing which is above it. Chemical stabilization is mixing the soil with certain materials to improve soil physical and mechanical properties such as development and the carrying capacity (CBR). Clay generally has a large development and soil bearing capacity (CBR) is relatively low, therefore it will be an examination of the clay from areas Kasongan, Bantul, Yogyakarta, stabilized using cement and DIFAŽ SS expected to improve and qualify a technical construction. Procedures were divided two stages: a preliminary study to determine the physical properties of the soil, initial testing includes moisture content, density and boundaries of consistency, having known physical properties of soil research is conducted the second stage of testing the mechanical properties of the soil. Testing of mechanical properties of soil covering proctor testing standards, after getting the optimum moisture content (OMC) and a maximum dry volume weight (MDD), and the addition of cement and DIFAŽ SS to the sample specimen with a large percentage of cement 8%, 10%, and 12 % of the dry weight of the sample volume, and 2.5% of the weight percentage DIFAŽ SS cement addition, CBR further testing and development of land. Results from the study showed that the stabilization of a mixture of 8%, 10% and 12% of cement by 2.5% DIFAŽ SS on one day curing properties change physical and mechanical properties are significant variations in the sample that had been in testing. In a variation of 8% PC + 2.5% DIFAŽ SS when compared to the native soil, indigo PI decreased by 37.04% where the original soil has a PI of 25% and 8% Variation PC + 2.5% DIFAŽ SS has a value PI 15.74%, its CBR value increased by 236.24% which the CBR value of the native land of 11.37% and a variation of 8% PC + 2.5% DIFAŽ SS has a CBR value amounted to 38.23%, the value decreases development 66.67% where the value of the original land development by 2.25% while the variation of 8% PC + 2.5% DIFAŽ SS development value of 0.75%. In a variation of 10% PC + 2.5% DIFAŽ SS when compared to the native soil, indigo PI decreased by 51.32% where the original soil has a PI of 25% and 10% Variation PC + 2.5% DIFAŽ SS has a value PI 12.17%, its CBR value increased by 263.50% which the CBR value of the native land of 11.37% and a variation of 10% PC + 2.5% DIFAŽ SS has a CBR value amounted to 41.33%, the value decreases development amounting to 81.33% where the value of the original land development by 2.25% while the variation of 10% PC + 2.5% DIFAŽ SS development value of 0.42%. In a variation of 12% PC + 2.5% DIFAŽ SS when compared to the native soil, indigo PI decreased by 74.64% where the original soil has a PI of 25% and 12% Variation PC + 2.5% DIFAŽ SS has a value PI 6.34%, its CBR value increased by 299.91% which the CBR value of the native land of 11.37% and a variation of 12% PC + 2.5% DIFAŽ SS has a CBR value amounted to 45.47%, the value decreases development amounting to 88.89% where the value of the original land development by 2.25% while the variation of 12% PC + 2.5% DIFAŽ SS development value of 0.25%. 
Keywords: Stabilization, Soil Clay, Cement, DIFAŽ SS, CBR.