The results of washing on treated soil with insecticides against subterranean termites Psammotermes hypostoma (Desnuax),indicated that, the first washed of treated soil were the highly efficacy and quicker in the killed against termites of all tested particle sizes than second and third, respectively, and the small particle size were the quicker and more toxic than others in the first washed of treated soil, while was the lower of toxic than others in third, second and first washed of soil, respectively. Also cypermethrin showed the highly toxic, followed by fipronil and chlorpyrifos, respectively. The treated coarse soil showed more toxic in the second and third than the fine, and to consider the lower safety to the water table, also the washed samples analysis indicated that, the chlorpyrifos showed the higher safety followed by fipronil and cypermethrin. Statistics analysis showed highly significantly between the factors treatments, number of washing and times, with the variable, (mortality %), while low significant recorded for particle sizes.