The interaction of hydrophobically random-modified and end-capped poly[2-(acrylamido)-2-methylpropanesulfonate]s, which are polyanions, with positively and negatively charged surfactants was investigated by steady-state fluorescence spectroscopy of labeled pyrene. The results revealed that both the polyanions interact with the positively charged surfactants more easily compared with the negatively charged surfactants although the polyanions do interact with the negatively charged surfactants due to hydrophobic interaction. Moreover, the end-capped polyanion had stronger electrostatic attraction with the positively charged surfactant compared with the random-modified polyanion.