Liquid waste generated from the testing activities COD(Chemical Oxygen Demand) in the laboratory containing Cr(VI) which is highly toxic and potentially pollute the environment . It required a processing method according to the characteristics of the waste. In this study examined removal of Cr ( VI ) using iron waste of electroplating industry. The goal is to get the best iron mass and temperature as well as determine the equilibrium constant according to Freundlich and Langmuir adsorption . The independent variables used are iron mass and temperature . Mass variation iron used is 0.5 g , 1 g , 1.5 g , 2 g , 2.5 g , while the temperature variation of 30 , 40 ° C , 50oC and 56oC . Fixed variable used is pH 2 , the contact time of 20 minutes and stirring speed of 120 rpm . Test levels of Cr ( VI ) was conducted using SNI 06-6989.53-2005 . The results revealed that the iron powder electroplating waste could reduce levels of Cr ( VI ) optimally on the addition of iron masses as much as 2.0 which is an average of 89.00 % at various temperatures . Optimal temperature that can reduce levels of Cr ( VI ) is the temperature 56oC with the percentage of 85.55 % . In this research, the equilibrium constant of Freundlich , KF is 4.1570 and n is 0.5685 with an error of 7.68 % , while the Langmuir equilibrium constant , qmax is -0.0434 and -6.4994 with bl is an error of 3.81 %