With appropriate wavelength selection, the contents of components in compound metronidazole tablets may be determined by signal multiplier spectrophotometry and the new solution of simultaneous equations in spectrophotometry without any preliminary separation. At the same time, the assay of compound metronidazole tablets was done using Hebei pharmaceutical standard. Determination results of the methods were tested by SPSS statistical software. It turned out that the results of the two new methods do not show significant difference, however, when compared with Hebei pharmaceutical standard, a significant difference exists. We think that there might be bigger errors in of Hebei pharmaceutical standard, because it has to undergo complicated preliminary separation. The new methods are simple, rapid and accurate, and are better than Hebei pharmaceutical standard.