The present invention belongs to the field of recovery of secondary resources of noble metals, and discloses a method for leaching platinum group metals from spent catalyst by UV-vis, which uses ferric oxalate complex/hydrogen peroxide-chloride salt solution as a solvent for extracting platinum group metals under the condition of UV-vis, converts the platinum group metals from metallic state to platinum group metal complex, and obtains platinum group metal lixivium to realize the leaching of the platinum group metals. The platinum leaching rate of the method of the present invention can reach more than 97%. The present invention has mild reaction conditions, realizes the green recovery of platinum group metals from spent catalyst, avoids the use of strong acids and bases and toxic substances and avoids the production of toxic gases in the leaching process, so as to reduce the environmental hazards of the spent catalyst.