The title compound, dicalcium nonaoxidodistannate(IV)dialuminate, is the second example which crystallizes in the isotypic structure of a pyroxene silicate, Na(2)Ti(2)Si(2)O(9) (ramsayite). (∞) (1)[Sn(2)O(8)] chains and pyroxene-type (∞) (1)[Al(2)O(6)] chains are formed along the b axis by sharing O atoms. The Ca atoms are situated in the resulting channels and exhibit a coordination number of 7.