Composite hollow building block (brick)

The utility model discloses a male-and-female type hollow block (brick) which comprises at least one cavity, at least one female block (brick) and at least one male block (brick), wherein the male block (brick) is projected on the large surface of the female block (brick) and extendable into corresponding cavity of another male-and-female type hollow block (brick). The male-and-female type hollow block (brick) is also arranged with at least one through or blind hole on the end face, separating rib, and strip face. Densely covered male-and-female dowels are formed in the wall body built by the male-and-female type hollow block (brick), thereby the anti-knock ability of the wall body is improved. The through or blind hole arranged on the end face, separating rib, and strip face of the female block (brick) not only reduces the self-weight of the wall body and facilitates the pipe and wire emplacement, but also saves the integrated cost of wall body construction.