A wet particle storage tank includes a tank body capable of storing wet particles containing particles and solvent. The tank body has an upper storage section having a supply port through which the wet particles are supplied, a lower storage section located below the upper storage section and having a discharge port through which the wet particles are discharged, and a bridge forming section provided between the upper storage section and the lower storage section. The bridge forming section facilitates formation of a bridge by the wet particles to block falling of the wet particles from the upper storage section to the lower storage section.