The invention relates to a sealing device of a continuous furnace hoister operation channel. A hoister (1) is provided with a support lever fork arm (3) extending into a continuous furnace (2), the continuous furnace (2) is provided with an operation channel (4) for vertical movement switching of the support lever fork arm (3), the sealing device comprises windshield plates (5), the windshield plates (5) are arranged on the support lever fork arm (3) and can vertically move along with the hoister (1), and when the windshield plate (5) vertically moves along with the hoister (1), one side of the windshield plate (5) always seals the operation channel (4). Compared with the existing sealing device, the sealing device provided by the invention can guarantee good shielding of a gap at the corresponding position through arrangement of the windshield plates at two sides of the gap of the operation channel (4) and movement of the windshield plates along with the hoister so that external cold air is not quickly inhaled in hoister descending and cracks caused by uneven heat and cold are produced.