An apparatus and method are provided to remove matte-sticking adhered to an inner surface of an inclined rear jacket of an exhaust gas hood for collecting exhaust gas discharged during the converter operation in copper smelting. Scraping means 10a˜10f are each provided with a scraping part 20 for scraping off matte-sticking by moving slidably across the inner surface of the rear jacket 8 by driving means 11 from a sidewall of the exhaust gas hood to at least over the centerline L of the width of the rear jacket 8. The scraping means are arranged in pairs at both right and left sidewalls of the exhaust gas hood 6 in multiple levels along the inclination of the rear jacket 8, thereby allowing the matte-sticking adhered to the rear jacket 8 to be removed over almost its entire surface.