The invention relates to the technical field of buildings, and discloses a historical building masonry wall reinforcing device and method. The scraping plate with the notch is arranged on the grouting
pipe, when the scraping plate slides towards the interior of the grouting hole, residual dust on the side wall of the grouting hole can be directly scraped away, residual
mortar generated by cleaning can be discharged through the notch in the bottom of the scraping plate, and it is effectively avoided that impurities in the hole interfere with combination of grouting liquid and building
brickwork; the problem of reinforcement failure caused by incomplete
impurity cleaning in traditional reinforcement is solved, in the grouting process, as the grouting hole is filled with grouting liquid, the pressure generated by the grouting liquid can push the scraper to move, the scraper can scrape the side wall of the grouting hole again in the process, residual
mortar is further pushed out, the cleanliness in the hole is ensured, and the grouting quality is improved. The situation that the solidification effect of the grouting liquid is affected by trace residual
mortar after primary cleaning is avoided, the grouting liquid fills the grouting holes more evenly, a more stable whole is formed by the grouting liquid and building masonry, the reinforcing reliability is remarkably improved, and the service life of a building is prolonged.