The waste soil at open dumping area is prone to settlement problems. There are many soil stabilization methods available that can be used to improve soil strength. The addition of egg shell powder and lime for waste soil improvement is studied in this research. Soil stabilization method using the waste material as replacement to improve the strength has been explored widely. In this research, the egg shell powder and lime is added to the waste soil with the mixing portion of 2.5% lime and 2.5% egg shell powder, 5% lime and 5% egg shell powder and 7.5% lime and 7.5% egg shell powder. The compressive strength is conducted on the waste soil samples with different mixing ratio. The optimum value of the compressive strength is simulated using Monte Carlo simulation. In conclusion, there is potential for the waste soil to be improved in terms of strength using lime and egg shell powder. The compressive strength of waste soil is added with 2.5% lime and 2.5% ESP, 5% lime and 5% ESP, 7.5% lime and 7.5% ESP gave the results of 36.39, 70.66 and 337.13 kN/mm2 respectively at curing of 28 days, which satisfies the soil improvement requirement. The Monte Carlo Simulation and optimization of the result using the mean value show that the compressive strength is increase when the data is simulated N = 16 to N = 20. It has proved that the accuracy of the result has increased by using Monte Carlo Simulation and optimization.