A device designed for the removal of soot dust of fuel oil combustion. The device is based on the two-stage wet-electrostatic dust removal-desulfurization device, with different numbers of layers of the mesh screen being installed in the wet type dust removal-desulfurization device. This device not only has a relatively high efficiency in both of common dust removal and desulfurization, but also can remove the black smoke from fuel oil combustion efficiently with a removal efficiency ≧99%, and thus solves the present technical problem in the treatment of in the treatment of soot dust of fuel oil combustion. At the same time, with the advantages of cheaper construction cost and economy, the device of the present invention overcomes the disadvantages of the traditional bag filter process, which is expensive and cannot operate desulfurization simultaneously.