A temporary embolic material for blood vessel which can embolize a blood vessel in a living body and is used for the temporary embolization of the blood stream. More specifically, disclosed is an embolus-forming material comprising a specific PVA particle which can be used for the closure of the inner lumen of a blood vessel by the PVA particle to embolize the blood stream, which can ultimately be absorbed in the living body, which can be excreted out of the body and which does not remain in the body. A pearl-like polyvinyl alcohol particle for use as a temporary embolic material, the particle having a saponification degree of 90 mol % or higher and an average particle diameter of 70 to 1000 μm and a temporary embolic material comprising the particle mixed or dissolved therein.