This paper deals with Metso’s Outotec Silver Electrorefining Process (Ag-ER) of Pd-rich Ag-anodes at high current density (HCD). Several Ag-ER tests with anodes containing up to 2% palladium were performed at anodic current density of 800–1200 A/m2. Apart from current density, the effects of other parameters, such as pH, temperature, and electrolyte flowrate, were studied to minimize palladium deportment to the refined silver. Thermodynamic calculations of the speciation of oxidized palladium in the electrolyte during Ag-ER were carried out. A major part of the oxidized palladium reports to silver anode slime as low-soluble hydroxide or oxide.