The pore structure of soil plays a decisive role in its engineering properties. In order to investigate the consolidation effect and pore distribution characteristic of saliniferous dredger fill after vacuum preloading, the indoor simulation experiments of vacuum preloading were carried out in two boxes, after vacuum preloading, the dredger fill was tested for its physicochemical and mechanical properties. Simultaneously, the mercury intrusion porosimetry was performed to obtain distribution of pore characteristic parameters, and analyzed its pore diameter distribution of dredger fill after vacuum preloading and the consolidation effect in the perspective of micro and macro. The research showed that the total pore volume and porosity of the No.1 box is lower than the No.2 box, and its bearing capacity and consolidation effect are much higher. When the dredger fill locates at the same distance from drainage plate, the deeper the dredger fill is buried, the smaller the porosity is, the better the bearing capacity and consolidation effect are. The pore of dredger fill in No.1 box is based mainly on meso pore, while the one in No.2 box is based mainly on meso pore and macro pore.