YbAgO2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Yb3+ is bonded to six equivalent O2- atoms to form edge-sharing YbO6 octahedra. All Yb–O bond lengths are 2.31 Å. Ag1+ is bonded in a linear geometry to two equivalent O2- atoms. Both Ag–O bond lengths are 1.99 Å. O2- is bonded to three equivalent Yb3+ and one Ag1+ atom to form a mixture of distorted corner and edge-sharing OYb3Ag tetrahedra.