The utility model discloses a deformation joint processing device for construction site advertisement enclosing walls. The deformation joint processing device comprises two angle iron and a plurality of aluminum-plastic fastening plates. The two angle iron are disposed along the extension direction of horizontal deformation joints or vertical deformation joints. Two ends of each aluminum-plastic fastening plate are respectively connected with the two angle iron. The aluminum-plastic fastening plates are disposed at intervals. A plurality of air discharge outlets are formed between every two adjacent aluminum-plastic fastening plates and the two angle iron. The processing device is simple and attractive, and harmony with the overall advertisement enclosing wall effect, and good air exhaust and discharge effects are achieved.