Application of multivariate curve resolution (MCR) is shown for three-way data obtained in acid-base titrations of salicylic acid monitored using emission spectrofluorimetry at three different excitation wavelengths. Rank analysis of augmented column-and row-wise matrices showed that the experimental fluorescent data have a trilinear data structure. MCR allows the unambiguous recovery of the species profiles in both orders: the fluorescent emission spectrum at each excitation wavelength and the pH distribution profile of the two fluorescent species formed during the acid-base titration. Results are compared with those obtained using the trilinear decomposition and generalized rank annihilation methods. Using the mass balance equation for the total concentration of salicylic acid, the third pH distribution profile of the non-fluorescent fully protonated salicylic acid species is deduced. The values of the two acid dissociation constants of salicylic acid, for the carboxylic and hydroxylic groups, are estimated without using the mass action law and are compared with previous estimations in the literature and with estimations using traditional mass action law hard-modelling-based methods.