The crystal structure of $K_5Na_2[SbW_6O_{24}]{cdot}12H_2O$ has been determined. Final R = 0.081 for 890 observed independent reflections collected by diffractometry. Crystal data as follows; trigonal, space group R3m, a = 9.794(1) ${AA},;{alpha}$ = 84.72$(1)^{circ}$, Z = 1. The heteropolyanion has a structure with point symmetry $D_{3d}$ (3m), of the ideal Anderson-type heteropolyanion. The Sb-W and W-W distances are 3.259(2) and 3.259(3) ${AA}$. Three types of W-O ($W-O_t,;W-O_b;and;W-O_c$) distances are 1.73(2), 1.95(4) and 2.20(3) ${AA}$. The Sb-O distance is 1.97(3) ${AA}$.