Crystal structures of stoichiometric and non-stoichiometric Sr-diphylloaluminosilicate phases are solved and refined using X-ray powder diffraction (XRPD) data by Rietveld method in trigonal space group P3¯c1 (No. 165) and hexagonal space group P6 3 /mcm (No. 193), respectively. The stoichiometric phase is synthesized from the Sr-LTA zeolite, whereas the non-stoichiometric phase is prepared from the Sr-FAU zeolite by thermal treatment. Structural models described in the space group P3¯c1 are refined to the agreement factors: R exp =3.32, R p =6.63, R wp =9.27, R B =3.70 for Sr-diphylloaluminosilicate LTA and R exp =3.64, R p =7.06, R wp =10.1, R B =3.76 for Sr-diphylloaluminosilicate FAU . Structural models described in the space group P6 3 /mcm are refined to the agreement factors: R exp =3.32, R p =6.50, R wp =9.10, R B =3.40 for Sr-diphylloaluminosilicate LTA and R exp =3.64, R p =6.92, R wp =9.90, R B =3.55 for Sr-diphylloaluminosilicate FAU . Vacancies in the positions occupied by the Sr 2+ ions are characteristic of the Sr-diphylloaluminosilicate FAU structure.