The invention provides an anti-seepage wall rapid construction device and a method. The anti-seepage wall rapid construction device comprises joint pipes, the joint pipes are provided with flexible joint pipe bodies, the bottoms of the joint pipe bodies are fixedly connected with a bottom plate, and the tops of the joint pipe bodies are fixedly connected with a top cover; a sealing cavity is constituted by the joint pipe bodies, the bottom plate and the top cover, the top cover is provided with a joint, the joint is used for being connected with a medium pipe, thus the joint pipes are filled with a pressure medium, or the pressure medium in the joint pipes is discharged. The method comprises the steps that during construction, the two joint pipes are placed at the two ends of a groove hole; the pressure medium is injected into the joint pipes, and a concrete wall is poured in the groove hole; and after the concrete wall is initially set, the pressure medium in the joint pipes is discharged, thus the diameter of the joint pipe bodies is decreased, and the joint pipes are hoisted to form a first groove section; and anti-seepage wall rapid construction is achieved. By adopting the joint pipes with the variable diameter and the small weight, the friction force between the joint pipes and the hole wall can be decreased, the self-weight of the joint pipes is decreased, drilling accidents in hole such as blockage due to tightly casting and pipe detaching are significantly reduced, and the situations that the joint pipes are overweight, and pipe drawing resources are excessively large in investment are avoided.