The invention provides a method for testing elements in a multi-element
system, a to-be-tested multi-element
system comprises N to-be-tested ions, and N is a positive integer greater than or equal to 2; a sample testing step: testing the to-be-tested multi-element
system by adopting a spectrophotometric method to obtain a sample analysis spectrum; a data reading step: respectively extracting sample
absorbance values corresponding to N wavelengths from the sample analysis spectrum; and an analysis and calculation step: substituting the sample
absorbance values corresponding to the N wavelengths into a standard light absorption equation, and calculating to obtain the
mass concentration of each to-be-detected
ion. According to the test method, when the standard light absorption equation is drawn, the single-component
standard solution is independently loaded in the
cuvette, so that valence state conversion caused by advanced mixing of multiple to-be-tested ions is avoided, and the
mass concentration of the to-be-tested ions in the multi-element system can be accurately obtained based on the test method.