The invention discloses a treatment device for exhaust gas produced during processing of a backlight assembly used for a LCM. The treatment device comprises an exhaust gas treatment tank, wherein an exhaust gas inlet shell is installed on the central part of one end of the exhaust gas treatment tank; a filter screen is arranged in the exhaust gas treatment tank and located at the end near the exhaust gas inlet shell; and a dust scraping component is installed on one side of the filter screen. The treatment device of the invention is scientific and reasonable in design, and safe and convenientto use; the dust scraping component is arranged, a motor is used for driving a threaded rod to rotate, and the threaded rod drives thread blocks to slide in two sides of the filter screen, so a dust scraping plate and a dust-cleaning soft brush are driven to clean dust accumulated on the surface of the filter screen; and thus, the filter screen can be cleaned irregularly, the filtering effect of the filter screen on impurities such as dust can be effectively improved, damage to the filter screen caused by frequent disassembling and cleaning of the filter screen is avoided, and the cleaning ofthe filter screen can be carried out at any time.