V Various development of the wastewater treatment process has been carried out to get maximum process of physical, chemical and biological. In this research, study has been conducted to acknowledge the influence of retention time or reaction time and voltage in an electrochemical process or electrocoagulation of domestic wastewater from Syarif Thayed Office Building (M), Trisakti University using contionuous and batch reactors. Variations in retention time in the electrocoagulation process of 12.5 VDC voltage using a continuous reactor is started from I; 3.6; 4; 4,9;10,1 and 57,2 minutes and one sample for each retention time treatment as standard without passing the electrocoagulation reactor for COD determination of initial or inlet. Output water from the reactor is being stirred using a jar test process in two stages, the rapid mixing stage at 200 rpm for 1 minute and slow mixing for 20 minutes at 20 -30 rpm speed, and then sample is decanted for 2 hours, then COD values measured using spektrofometer and TSS using gravimetric method for clear water sample. COD obtained from 55 % - 73 % with varying inlet COD concentration 141 mg/L -432 mg/L and TSS indecanter water 2-50 mg/L and for standard sample 10 - 143 mg/L. Electrocoagulation process using batch reactor with a reaction time of 0, 10, 20, 30, 40 and 60 minutes is done on voltage 2,3,4 VDC, and current 0,1 - 0,63 A with stirring and decanter time is same with continous system and the pH of the water is mantained 6.8 - 7 and the reduction in COD concentration dropped rapidly after electrocoagulation process for the first 10 minutes with a range of 85 % for all three voltages and a decrease in COD concentration declined slowly for electrocoagulan time after 10 minutes and at 60 minutes electrocoagulation time after 10 minutes and at 60 minutes electrocoagulation exluded COD by 93-95 % , with initial COD 541 mg/L