The invention provides a wall module and a shear wall. The wall module comprises an inner template and an outer template, wherein the inner template and the outer template are integrally connected through connecting rib plates, and a reinforced concrete pouring cavity is formed between the inner template and the outer template. The shear wall comprises the wall modules, a wall template is splicedby the wall modules, rebars are arranged and concrete is poured to the cavities formed between the inner templates and the outer templates, and inner and outer protective layers are arranged on the outer sides of the inner templates and the outer templates. The wall module serves as a template system during construction of the shear wall, so that the complicated process for constructing and removing a support template is omitted, and template waste is avoided. The wall module serves as an insulation layer after construction of the shear wall, a sandwich type double-layer insulation shear wallis formed, and a stress bearing main body and the insulation layer are constructed once. The construction process of the shear wall can be simpler, the cost is reduced, and the construction progress is faster.