Ultrasound-assisted activation is developed to improve the adsorption property of coal-based electrode materials.Scanning electron microscopy (SEM) is used to analyze the morphology and surface structure of coal-based electrode materials.N2 adsorption method is used to measure materials' pore size parameters.It is found that with the increase of KOH content, the compressive strength of coal-based electrode materials tends to decrease while the iodine adsorption value gradually increases up to 741.44 mg·g-1.Ultrasound assisted conditions can strengthen this change rule.The coal-based electrode material with a KOH addition of 15% and under ultrasound assisted conditions is selected as the adsorption treatment material for cyanides-containing wastewater.This material has a specific surface area of 386 m2·g-1, a total pore volume of 0.192 cm3·g-1, a micro-pore volume of 0.170 cm3·g-1 and a micro porosity of 88.31%.It is set as the anode and cathode in a three-dimensional electrode system to treat with cyanides-containing wastewater.The removal rate of every ion in the wastewater exceeds 95% when voltage is 4 V and adsorption time is 4 h.