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As the primary active components of automotive three-way catalysts, precious metals play an important role in purifying auto-exhaust. However, the charge of the precious metals in their precursor compounds, the bond intensities between precious metals and the ligands, the precursors solution pH values and whether other ions exist in them or not, directly influence dispersion of the precious metals on the modified material and interaction between the precursor and the material after activation treatment. Consequently they affect the performance standards of the catalyst activity, high-temperature stability, durability and so on. According to the review of the precious metals precursor researches at home and abroad, the important effects of the species and applied conditions of precious metals precursors on the catalyst performance are clarified, and it is thought that making full use of them to guide the high cost-effective catalytic material development are of great importance.