The technology of electrkinetic remediation was used to treat lead and cadmium composite contaminated soil. The effects of electrolytes such as disodium ethylenediamine tetraacetic acid (EDTA), citric acid and citric acid + calcium chloride on the removal of Pb and Cd were investigated. The migration mechanism of Pb and Cd under different electrolyte conditions was explored. The results showed that the removals(%) of Pb were 14.70%, 11.6% and 17.01%, the removals(%) of Cd were 22.84%, 15.08% and 23.3%, and the power consumption was 29.3, 37.8, and 50.3 (kW·h)/g, respectively, with a voltage gradient of 2 V/cm, a remediation time of 96 h and electrolytes of EDTA, citric acid and citric acid + calcium chloride. Combined with the distribution of Pb and Cd in the remediated soil and the simulation results, it was indicated that EDTA migrated to the anode by complexing with Pb2+and Cd2+into PbEDTA2-and CdEDTA2-. While acidifying the soil, citric acid complexed with Pb2+and Cd2+into PbH2-Citrate+, CdH2-Citrate+, Pb-(Citrate)4-2and Cd-(Citrate)4-2, migrated to both poles and focused in the middle of the soil. Under the action of citric acid, Cl-in calcium chloride formed complexes PbCl+and CdCl+with Pb2+and Cd2+, further promoting desorption and improving the removal of Pb2+and Cd2+.