A series of laboratory tests were conducted to verify the unhardening phenomena of Soil-Cement Wall (SCW) and the results are presented in this paper. Specimens are prepared by mixing the site soil with cement and additives at a various ratio. The hydration of the cement mixed with the in-situ soil was retarded due to the higher organic content of the soil. In order to remove the influence of the organic matters in hydration reaction, calcium chloride (CaCI$_2$) was added as an acceleration additive at a different ratio. The optimum ratio of the calcium chloride for the higher SCW strength was determined as 2% of cement weight. The strength, however, was decreased by adding 4 and 6% of the additives. The effect of other additives, NaOH and NaSiO$_2$, were also investigated and the results are included. The strength of SCW by adding sodium hydroxide was lowered. And the short term strength by adding sodium silicate was increased but the long term strength was decreased.