In the present research, electrocoagulation, ultrasonic, and simultaneous application of both methods were investigated to remove humic acid (HA) from wastewater. For the electrocoagulation method, the effects of five combinations of platinum, graphite, and aluminum electrodes, pH, time, voltage, temperature, and concentration of electrolyte on removal efficiency were evaluated. Results revealed that the combination of Pt (anode)/Al (cathode) at neutral pH, 10 V voltage, 0.02 M concentration of electrolyte support, and temperature of 25°C had the best removal efficiency. Under optimum conditions the maximum removal efficiency of HA at 15 min by Pt/Al and without ultrasonic wave was 96.5%. Finally, it was found when ultrasonic used simultaneously with electrocoagulation, the removal efficiency decreased drastically. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 822–829, 2017