The invention discloses a deicing device for a 330KV power transmission line, and relates to the technical field of power transmission lines. The device comprises a box body, an ice receiving groove is formed on the upper surface of the box body, and a flow guide pipe is arranged on the lower surface of the box body. A left side plate and a right side plate are fixedly installed at the positions,located at the two sides of the ice receiving groove, of the upper surface of the box body correspondingly, a deicing cavity is formed by the left side plate and the right side plate, and a heating mechanism is arranged in the deicing cavity. The deicing device is scientific and reasonable in structure and is convenient to operate; with the arrangement of the heating mechanism, the power transmission line can be preheated and de-iced, and the subsequent deicing work is facilitated; with the arrangement of an ice crushing mechanism, the ice blocks preheated by the heating mechanism can be crushed, and the deicing work of the power transmission line is achieved; with the arrangement of an ice scraping mechanism, the ice blocks crushed by the ice crushing mechanism can be scraped. The deicingdevice integrates heating, crushing and scraping functions as one and is better in deicing effect.