Recently, extensive research on soil and groundwater remediation has demonstrated surfactant (surface active agents) flushing to be a viable alternative for improving the efficiency of pump-and-treat remediation. Column tests were carried out to examine the effect of surfactant solution conditions on surfactant-enhanced remediation of soil columns contaminated by 1,2,4-trichlorobenzene (TCB). An Iowa Fruitfield soil was used for this study and sodium diphenyl oxide disulfonate (DOSL) that is an anionic surfactant was selected in this research. The conditioned parameters of the surfactant solution for the column tests were concentration, pH, temperature and flow rate. The test results revealed that an optimum condition was achieved for 4% (v/v) of concentration, pH 10, 20°C of temperature and 4 mL/min of flow rate, respectively. The removal of 98% of TCB was obtained with combination of optimal conditions of surfactant solution with NaCl. This was a marked improvement and removal efficiency increased by 4–17% compared to that with unadjusted (not optimum) conditions. The optimum range of these parameters may be useful for surfactant-based remediation in soil contaminated by TCB.