Ag-Ti nanocomposite materials have drawn increasing research attention because of their superior catalytic properties. However, the preparation of a crystalline Ag-Ti material is an important challenge in synthetic chemistry. Herein, we report a family of atomically precise Ag-doped polyoxotitanium nanoclusters (PTCs) (PTC-253-PTC-256) with a size of 19.56 x 19.02 angstrom. Each Ag-PTC is made up of a tiny Ag-2 kernel and a double-decker Ti-12 nanowheel as well as an organic protective shell. Hence, they can be regarded as Ag-2@Ti-12@(L)(14)(OMe)(n) unique triple core-shell structures. Notably, the peripheral organic shell can be modified with different benzoate derivatives. With precise atomic information, these compounds can be used as ideal molecular models of Ag-Ti nanocomposite materials for studying the growth or reaction mechanism via theoretical calculations. Meanwhile, a PTC-255-modified electrode presents efficient electrocatalytic CO2 reduction activity with a Faradaic efficiency (FE) of 29.4%. This work demonstrates that Ag-doped crystalline PTC materials are promising candidates for application to the electrocatalytic CO2 reduction reaction (CO2RR).