Silk fabric was dyed with a hemicyanine dye, DHEASPBr‐C4, to create the fluorescent silk fabric in this article. The study initially focuses on the dyeing properties of the dyed silk fabric, followed by the reflectance and emission spectra. The results show that the sorption isotherms are the Langmuir type and the dyed silk fabrics using DHEASPBr‐C4 have an obvious fluorescent effect in the spectral range 570–720 nm, while their peak locations of ca. 590 nm in the emission spectra are under the excitation of 365 nm. Finally, the CIE coordinates of the dyed silk fabric are discussed in order to investigate further potential applications.