Present study explores the interaction of biologically important dye, acridine orange (AOH⁺), with biomacromolecular host, DNA, under two extreme salt (NaCl) concentration conditions, i. e., physiologically relevant 0.15 M NaCl and highly concentrated 4 M NaCl, following various photophysical measure-ments. In the presence of the salt, the AOH⁺-DNA system shows contrasting modulations in the photophysical properties than those reported earlier in the absence of the salt. Thus, without any salt addition, the AOH⁺undergoes a drastic fluorescence quenching at the lower DNA concentrations, due to dye dimerization on DNA surface, but experiences a huge fluorescence enhancement at higher DNA concentrations, owing to monomeric dye-DNA intercalative complex formation. Contrastingly, in the presence of the salt, we observe only large fluorescence enhancement for AOH⁺all along the DNA concentrations used. Critical inspection of the results reveal that at 0.15 M NaCl, the monomeric form of AOH⁺undergoes both DNA surface binding and intercalation between DNA base pairs. At 4 M NaCl, however, there is mostly the intercalative binding of AOH⁺ with DNA host. Interestingly, in the fluorescence anisotropy study, we observe the intriguing dip-rise-dip features in the anisotropy kinetic traces, rationalized considering dynamic variations in the fluorescence intensity and anisotropy contributions of the free and the DNA-bound AOH⁺ species present in the solution. Present study provides the details of the salt-induced modulations in the photophysical properties of AOH⁺ upon its interaction with DNA host, thereby revealing the intriguing insights of the binding mechanisms involved in the present systems. Observed results would expectedly be useful in bio-analytical chemistry, pharmaceuticals, drug formulations, drug delivery, functional materials, and similar other applications.