Abstract: A particle measuring device includes a probe including a nozzle spraying a gas on a surface of an object and an inlet inhaling the gas and particles scattered from the surface by the gas; a main pipe including an inflow hole through which the gas flows and a discharge hole through which the gas is discharged; a first manifold provided to connect the main pipe to the nozzle, and supplying the gas to the nozzle; a second manifold provided to connect the main pipe to the inlet between a connecting portion of the first manifold and the discharge hole, and supplying the particles and the gas to the main pipe; a third manifold branched from the second manifold and supplying the particles and the gas; and a particle counter connected to the third manifold, and counting the particles included in the gas supplied through the third manifold.