Аннотация:The effect of the ratio of Ca2+ and Cd2+ in the compounds of Ca2-xCdxSb2O7 on the structure of synthesis products at 800°C, 2 kbar in water is studied. It was shown that the introduction of a significant amount of Ca2+ into the compound causes structural transformations of (cub. sing.)--> Imma (orthorhombic sing.). The influence of the mole fraction of Ca2+ on the parameter of the unit cell of pyrochlore (romeite) is considered.