Abstract. This research aims to study the optimum effect of contact time and pH adsorption of copper (Cu 2+ ) from electroplating industry waste by dried beer waste S.cerevisiae. This research conducted using batch culture with pH variation 2,3,4,5, and 6, contact time variation 60, 90, 120, 150, 180 minutes, 150 rpm at room temperature (± 28°C), initial Cu 2+ concentration 33,746 mg/l, and biosorbent mass 200 mg & 500 mg. The adsorption of heavy metal ions Cu 2+ occurs in all variations of pH and contact time at optimum pH. The optimum adsorption occurs at pH 4 with contact time 120 minutes for both 200 mg (41.60%) and 500 mg (61.04%) beer waste biosorbent. Cell morphology seen with Scanning Electron Microscope (SEM) analysis shows the change of cell wall that gets damaged from Cu 2+ adsorption. It also proved by the decreased concentration of initial high concentration carboxyl groups. The adsorption process of this research complies to Freundlich Isotherm with R 2 value closest to 1 and followed first order kinetic. Keywords: contact time, copper, pH adsorption, S.cerevisiae IntroductionVarious research regarding metal ion reduction treatment has been done, such as oxidation-reduction, precipitation, adsorption, compaction, electrolytic recovery, and ion exchange. These processes are expensive in which some technological problems exist especially when applied to diluted metal solutions. Therefore, the search for clean and competitive technologies is strongly recommended. Biological treatment is usually considered as an effective method and can significantly reduce the quantity of heavy metals in aqueous solutions [1]. Study of biosorption as an alternative treatment considered effective in cost and easy to apply. Biosorption can adsorb more heavy metals than chemical precipitation on bigger pH range [2]. Biosorption capacity is mainly influenced by three kinds of influential factors: metal ionic characteristics (e.g., atomic weight, ion radius, valence) the nature of the biosorbents (e.g., cell age), and biosorption conditions (e.g., pH, temperature, contact time) [3].This research aims to study the effect of contact time and pH to adsorption of Cu 2+ ion by biosorbent S. cerevisiae, determine the adsorption efficiency of Cu 2+ ion contain in electroplating wastewater by biosorbent S. cerevisiae, and determine functional groups involved in Cu 2+ adsorption process.