The phase diagrams of following binary soap systems (soap = K-myristinate = KC14) were examined by polarization microscopy: system KC14/glycerol (G), KC14/ethylene glycol (E) and KC14/butylene glycol (E). Comparing these three phase diagrams, we found alterations in types of phase diagrams that depends on the chemical structure of the solvent. The following polymorphism were observed: In the system KC14/G: C↭G↭H↭I↭L↭S (C = crystalline phase, G = gel phase, H = hexagonal phase, I = isotropic phase, L = lamellar phase, S = isotropic solution). In the system KC14/E: C↭G↭L↭S and in the system KC14/B the same phase sequence: C↭G↭L↭S.