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Surface adjustment is an important process in the phosphating process before painting， and its effect directly affects the phosphating crystal morphology. In order to clarify the adsorption property of surface conditioning agent for phosphating on the surface of high strength steel，the exsisting state of elements on the surface of high strength steel was analyzed by X-ray photoelectron spectroscopy (XPS)，scanning electron microscope (SEM)， focused ion beam (FIB) and transmission electron microscope (TEM)， and the adsorption properties of oxides on the surface of high strength steel to the surface conditioning agent particles were analyzed by absorption kynetic experiment. Furthermore， a brief phosphating treatment was performed on the surface of the high strength steel after surface adjustment to examine the initial nucleation state of phosphate. Results showed that the oxides with the highest contents on the surface of high strength steel were Fe2O3 and MnO. Compared with Fe2O3， MnO had a stronger adsorption capacity for surface conditioning agent particles， and could adsorb surface conditioning agent particles preferentially in competitive adsorption. Combining the above-mentioned results with the morphology and element distribution of the surface and cross section of the high-strength steel， it could be proved that the MnO on the surface of the high strength steel was the key to the adsorption of surface conditioning agent particles， and the initial deposition of phosphate occurred at the sites with the surface conditioning agent particles.