The invention discloses a chitosan packaging film and a preparation method thereof, belonging to the technical field of high polymer material preparation. The preparation method comprises the following steps: mixing chitosan powder with acetic acid solution, standing, swelling, heating and dissolving, thereby acquiring a chitosan solution; mixing phospholipid, chloroform, calcium nitrate solution,olive oil, modified pearl powder and polyvinyl alcohol solution and ultrasonically dispersing, thereby acquiring a dispersing solution; mixing the acquired chitosan solution with the acquired dispersing solution and stirring, thereby acquiring a film-forming solution; vacuumizing the acquired film-forming solution and removing air bubbles, pouring the film-forming solution without air bubbles onto a horizontal glass plate, drying and forming a film, thereby acquiring a film blank; dipping the acquired film blank into a calcium bicarbonate solution, hermetically reacting under constant temperature, cooling, taking out and drying, thereby acquiring the chitosan packaging film. The chitosan packaging film provided by the invention has excellent mechanical properties.