An infrared detector with a multi-layer structure based on a CMOS process. A CMOS measuring circuit system and a CMOS infrared sensing structure in the infrared detector are both fabricated by using the CMOS process, and a CMOS manufacturing process comprises a metal interconnection process, a through hole process, an IMD process and an RDL process. In the infrared detector with the multi-layer structure, a first columnar structure comprises at least one layer of solid columnar structure and/or at least one layer of hollow columnar structure, a second columnar structure comprises at least one layer of solid columnar structure and/or at least one layer of hollow columnar structure, at least one hole-shaped structure is formed in an absorption plate, and the hole-shaped structure at least penetrates a dielectric layer in the absorption plate; and/or, at least one hole-shaped structure is formed in a beam structure.