This study investigated the removal effectiveness and mechanism of mixed surfactant solutions composed of sodium dodecyl sulfate (SDS) and polyethylene glycol octylphenyl ether (TX100) on trichloroethylene (TCE) contamination through column and three-dimensional sand tank experiments, combined with electrical resistivity tomography (ERT). The column experiments revealed a significant synergistic effect of surfactant concentration and mixing ratio on TCE removal. When the mixing ratio α was 0.9, all tested concentrations exhibited optimal removal performance, with the 3.0g/L solution showing the highest resistivity change percentage (91.37%), followed by 1.5g/L (87.07%) and 0.5g/L (81.25%). Resistivity monitoring indicated that most TCE removal occurred during the first pore volume (pv) of surfactant injection, after which the resistivity stabilized, suggesting the completion of the removal process. In the sand tank experiments, the resistivity difference in the TCE-contaminated region increased from an initial value of approximately 60 Ω·m to 120~140 Ω·m during TCE injection, reflecting the accumulation of contaminants. After water injection, the resistivity difference decreased to 30~60 Ω·m with a localized rebound to 80~140 Ω·m, indicating dilution and redistribution of the contaminant. Following the injection of the mixed surfactant solution (3.0g/L, α = 0.9), the resistivity difference in the contaminated area significantly decreased to the initial range (approximately 20~60 Ω·m), demonstrating a remarkable removal effect. ERT effectively visualized the contaminant removal process in real time, revealing spatial distribution changes of TCE across different depths and cross-sections. This non-invasive, real-time, and three-dimensional monitoring approach highlights the unique advantages of ERT in tracking and evaluating contaminant remediation processes.