First fixed pigment volume concentration (PVC) was 15%, the zinc phosphate as antirust pigment, wet sericite powder as the inert pigment, with liquid polysulfide rubber (LP3) of modified epoxy resin (E51) as coating substrate, the preparation of modified polysulfide epoxy anticorrosive paint, testing the basic physical properties of the coating, respectively, by means of metallographic microscope and scanning electron microscope (SEM) to observe the surface morphology of coating and the cross section morphology, at the same time using electrochemical impedance spectroscopy (EIS) technique to explore the antirust pigment content on the properties of modified polysulfide epoxy anticorrosion coating. The influence of pigment volume concentration (PVC) on the anti-corrosion performance of polysulfide modified epoxy coating was investigated by electrochemical impedance spectroscopy (EIS). The results show that with the decrease of the content of zinc phosphate in antirust pigment, the time of the corrosive medium penetrating through the coating is prolonged, and the time of the corrosive medium remaining on the metal interface between coating and substrate is shortened. The anticorrosion performance of the coating reaches the best when the content of antirust pigment is 60%. When PVC≤20%, the anticorrosion performance of the coating increases with the increase of PVC, and when PVC≥25%, the anticorrosion performance of the coating decreases rapidly, so the critical pigment volume concentration (CPVC) of the system is between 20%~25%. In this system, when the content of antirust pigment is 60% and the volume concentration of pigment (PVC) is 20%, the coating has good physical properties and excellent anticorrosive performance.