X-ray fluorescence analysis software Spectra Plus was used to calculate theoretical alpha influence coefficents of other elements to Cr in seven stainless steel standard samples, theoretical alpha influence coefficients of elements, by which Cr signal was enhanced, varied largely with the change of elements content. Variable theoretical alpha influence coefficients, which varied with elements content, were used to correct the matrix effects in stainless steel, the secondary excitation of Cr by other elements were corrected, and Cr (0.3%-20.8%) in stainless steel and low alloy steel could be analysed in accordance with one calibration curve. The matrix effects in samples can be corrected by variable theoretical alpha influence coefficients, so the measurable content range of calibration curve was enlarged. The contents of fifteen elements Al, Si, P, S, Ti, Cr, Mn, Co, Ni, Cu, As, Mo, Sn, W and Pb in stainless steel were measured by X-ray fluorescence spectrometer, variable theoretical alpha influence coefficients were used to correct the matrix effects, and the analysis results are comparable to those obtained by wet chemical method.