Laser-induced breakdown spectroscopy (LIBS) combined with conventional tablet preparation methods for detecting cadmium (Cd) content of rice has low sensitivity. This study proposes to use a film sample preparation method to improve the sensitivity of LIBS to detect the Cd content in rice. A rice film sample was prepared after scraping the rice suspension onto a glass slide, and the feasibility of using the film sample to improve the sensitivity and accuracy of Cd content detection in rice was discussed. For the tablet and film samples, the spectrometer's delay time and laser energy were improved, and the reasons for the inconsistency of the optimal laser energy were analyzed. After optimizing the experimental conditions, the differences between the LIBS spectra of the tablet and film samples were compared, and the principle of film enhancement was analyzed through experiments. The Cd-spectrum intensity of film preparation increased 5-7 times compared to the conventional tablet preparation, and the detection limit is reduced by 1/9. The method of film preparation improves the ability of LIBS technology to detect Cd content in rice.