In order to investigate the application of dyes in the field of textile dyeing, the interaction between pyronine G (PG) and sodium dodecyl sulfate (SDS) was studied by spectral method. The results showed that the fluorescence quenching of PG appeared when it reacted with the monomer of SDS. A new stronger fluorescence peak was obtained when it reacted with the micelle of SDS. Meanwhile, the influence of Na2SO4 and (NH2)2CO on the interaction between PG and SDS was investigated. The interaction between PG and SDS became stronger in the presence of Na2SO4 but became weaker in the presence of (NH2)2CO. And the interaction mechanism was also discussed by absorption and fluorescence spectra.