The invention provides a liquid-based cell preparation device and method and a film cylinder for liquid-based cell preparation.The liquid-based cell preparation device comprises a lifting arm, a preparation part and a moving station part, wherein the preparation part is arranged on the lifting arm and comprises film cylinder connection parts arranged in the moving direction of the lifting arm; the moving station part comprises one or more station sets, each station set comprises a sample base for storing sample liquid of liquid-based cells and a glass slide base for holding a glass slide, the moving station part can move to enable the sample bases and the glass slide bases to move the working positions corresponding to the preparation part, and when located at the working positions, the sample bases and the glass slide bases are located on moving paths of the film cylinder connecting parts or extension lines of the moving paths.The moving station part can enable multiple stations arranged on the moving station part to move to the working positions corresponding to the preparation part, and therefore the automation degree of the preparation procedure is improved, proportion of manual operation for preparation is reduced, that is, the preparation procedure is simplified, and the preparation efficiency is improved.