To improve the durability of a shaft sealing device by preventing the entry of fluid to be delivered including solid particles into a shaft sealing portion, even under the condition having large pressure fluctuation wherein high pressure is instantaneously and intermittently generated.

In this pump shaft sealing device, stop rings 4A, 4B and plural seal rings 5A, 5B are respectively installed in a fluid to be delivered side and an atmosphere side of the shaft sealing portion of a volute pump, and a greasing hole 10 for greasing the inside of the shaft sealing portion is provided between the seal rings 5A, 5B. Behind the seal ring 5B, pressurizing holding seals 8A, 8B, 8C, 8D are provided, which have an elastic lip with large spring constant and high hardness on inner and outer peripheral surface thereof, and is sealed by opening the elastic lip inward and outward at the time of high pressure load operation.