The interaction of SDBS in aqueous gelatin solutions is studied above the gelation temperature by viscosity and circular dichroism (CD) measurements. The steep rise in the relative viscosity of the system could be due the structural transitions leading to micellar growth of higher orders, which is supported by CD measurements. The circular dichroism spectra indicated that gelatin helped in inducing the sphere -> rod transition, without suffering any conformational changes within it. The large changes in viscosity over the concentration range studied points to the strong molecular interactions in gelatin-SDBS system and its dependence on [SDBS]. CD spectra showed an increase in ellipticity, suggesting that the micelle can either bind intra molecularly, i.e. within a gelatin molecule, or it can bind cooperatively with two or more molecules to form a large complex. The findings are particularly significant in terms of the head group contribution, hydrophobic interaction and formation of formulated complexes.