To prevent tin from sticking to a surface of an object to be soldered where a solder bump is formed.

The reflow pretreatment device includes hydrogen radical generator 3, and a suspended substance capturing filter 5. The hydrogen radical generator 3 radiates hydrogen radical to a solder disposed on a soldering object 10. The suspended substance capturing filter 5 is arranged so that a hydrogen radical goes through the suspended substance capturing filter 5 before it is radiated to the solder. The solder is, when irradiated with hydrogen radical, gotten rid of an oxide film formed on its surface, and releases a suspended substance that has been liberated from the solder. The reflow treatment device like this captures the suspended substance by the suspended substance capturing filter 5, thereby preventing the suspended substance from depositing on the surface of the solder object 10.