The interactions of FD & C Red No.3 (erythrosine) in 1 or 2% concentrations with various types of pharmaceutical gelatins were studied. In visible region spectroscopy type A gelatin showed 6 nm bathochromic shift in ${lambda}_{max}$ of erythrosine, but no shifts were observed in other gelatins. Various results were obtained in the decrease of absorbance from 0.06 to 0.25. In dissolution study, the gelatin that showed the greatest spectral change exhibited the worst profile. From above results, it is concluded that erythrosine interacted to the greatest extent with type A gelatin and in the case of type B gelatin the degree of the interaction in different according to their specifications.