As an important strategic reserve metal, palladium (Pd) is widely used in chemical, automotive catalysts, aerospace and electronic products due to its excellent physical and chemical properties. However, due to the lack of mineral resources, it is difficult to meet the needs of social development, so it is of great significance to study the secondary recovery process of Pd to realize the recycling of Pd. In this work, a new leaching system of Ce(NH4)2(NO3)6 was proposed to solve the problems existing in the traditional leaching system. The dissolution behavior of Pd powder in acidic Ce(NH4)2(NO3)6 solution was studied in detail. The results showed that the dissolution of metallic Pd in the mixed system was significantly affected by the adsorption on the Pd surface. In the absence of Cl-, the surface of metallic palladium was passivated by the adsorption of oxygen or NO3- on the surface, which hindered the reaction between Ce4+ and Pd atoms since the dissolution ratio was only 0.2% in 5 h. The addition of Cl- was helpful to destroy the surface passivation layer through competitive adsorption and accelerated the dissolution reaction of Pd. The NO3- and Cl- constituted competitive adsorption, and higher concentrations of nitrate required higher concentrations of Cl- to initiate the dissolution reaction. The effects of different reaction conditions on the dissolution efficiency of Pd powder were investigated. The results showed that the efficiency of the dissolution of Pd powder reached 100% after 1.5 h at the concentration of Ce(NH4)2(NO3)6 of 1 mol/L, HNO3 of 1 mol/L, Cl- of 0.03 mol/L, reaction temperature of 80℃ and stirring speed of 200 r/min, which was the preferences condition of the dissolution of Pd powder. The dissolution kinetics of Pd powder in acidic Ce(NH4)2(NO3)6 solution showed that the dissolution reaction of Pd powder in solution conformed to the shrinking core model controlled by chemical reaction. The apparent activation energy of the dissolution reaction was 58.7 kJ/mol, and the kinetic equation was 1-〖(1-x)〗^(1/3)=2264806e^(-58732/RT) t.