The invention discloses a one-time plugging device for water leakage of a building. The one-time plugging device for water leakage of the building is directly driven into a wall, and not only can deodorization and sterilization be achieved, but also a water seepage gap in the wall can be plugged through grouting. The plugging efficiency of the gap inside the building wall can be improved effectively, and the cost is saved. The one-time plugging device is characterized in that an inner connecting pipe is placed at one end of a main body cylinder; an outer connecting pipe is placed on the innerconnecting pipe in a sleeving mode and is in threaded fit with the inner connecting pipe; a pin cap is placed on the outer connecting pipe and is of an annular platy structure; a rubber cushion is placed on one side of the pin cap, and a clamping hook is arranged on the other side of the pin cap; the main body cylinder is provided with a plurality of diffusion holes in the axial direction; a rubber ring is arranged on the main body cylinder in a sleeving mode and is close to the other end of the main body cylinder; the main body cylinder is made of a rigid material; a partition ring is placedon the inner circle of the pin cap and provided with a plurality of through holes; and one end of a connecting pipe is placed on the pin cap, provided with an observation hole and internally providedwith a filter sponge, and a cover plate is placed on the connecting pipe.