The invention discloses a deformation joint double-layer shear wall formwork structure which comprises four layers of wooden templates, wherein a first outer side wooden template and a first inner side wooden template surround and form a left side shear wall pouring working layer, a second outer side wooden template and a second inner side wooden template surround and form a right side shear wall pouring working layer, a wall penetrating bolt penetrates through the first outer side wooden template, the second outer side wooden template, the first inner side wooden template and the second inner side wooden template, steel sliding grooves are vertically formed every certain distance in the inner side of the first inner side wooden template and the inner side of the second inner side wooden template, strip-shaped steel boards are arranged corresponding to the steel sliding grooves on the outer side of the first inner side wooden template and the outer side of the second inner side wooden template, and steel channel keels are inserted inside every two steel sliding grooves which are oppositely formed. The invention further provides a method of constructing a double-layer shear wall. The structure enables the shear wall formed by pouring to be in order and better in quality, capable of being repeatedly used, good in economy and good for popularization, the whole construction progress is safe and convenient, and the time and the labor cost are favorably reduced.