To solve problems in a conventional work bench that as the work bench does not have a function to absorb and extinguish the spark produced in grinding work, the spark often causes the fire, which is dangerous, and the circumference is contaminated.

A plate as a top plate 2 having a number of holes 2a is openably and closeably mounted on an upper end part of a work bench case 1, a dust collecting part 4 and an exhausting device 9 for exhausting the air in the dust collecting part 4 are mounted in the work bench case 1, the dust collecting part 4 is composed of a bag filter 6, and a water tank 7, a guide cylinder 8 or the like mounted in the back filter 6, the fired dust is brought into contact with a water surface to be extinguished and splashed, or dipped into the water to be settled into the water tank 7, and the extinguished dust is collected by the bag filter 6.