The invention is configured so that pressurized gas from a pressurized gas supply source passes through a pressurized gas channel provided in a main body of a powder spraying device and is sprayed out. A powder container containing powder such as medical agents is provided on the main body. The powder within the powder container is supplied to the pressurized gas channel and is sprayed together with the pressurized gas. An eccentric rotor with a center of gravity deviated from a center of rotation is provided in the main body. When spraying the powder together with the pressurized gas, vibrations are applied to the main body and the powder container by a rotation of the eccentric rotor. The powder can be thereby mixed more evenly with the pressurized gas.