Radix Salviae miltiorrhizae powder contains dozens of chemical constituents and is a typical multicomponent substance that is difficult to analyze quantitatively using traditional two-dimensional fluorescence spectroscopy. In this study, three-dimensional synchronous fluorescence combined with parallel factor algorithm, the split half method, and sum of squared error analysis were used to study the fluorescence characteristics of multicomponent Radix Salviae miltiorrhizae powder. The parallel factor model of a Radix Salviae miltiorrhizae powder solution was identified as four components. The corresponding component fluorescence characteristics were as follows. The first component synchronous fluorescence peak in this region was λ_Ex = 470--480 nm, λ_Em = 520--530 nm, and the second component synchronous fluorescence peak in this region was λ_Ex = 400--410 nm, λ_Em = 490--500 nm. The third component synchronous fluorescence peak in this region was λ_Ex = 370--380 nm, λ_Em = 460--470 nm, and the fourth component synchronous fluorescence peak in this region was λ_Ex = 560--570 nm, λ_Em = 620--630 nm. The fluorescence characteristic of the second component may be the fluorescence of salvianolic acid B. Experimental results demonstrate that the three-dimensional synchronous fluorescence method combined with the parallel factor algorithm has a distinct advantage for fluorescence spectroscopic analysis, especially for a complex multicomponent substance coupled with a more interfering substance. This study can provide a reference for the analysis of multicomponent of Chinese patent medicine.