Size-induced particle segregation during the silo filling process greatly changes the electrostatic charge distribu-tion, influencing the occurrence of the incendiary electrostatic discharge. However, few studies concern the elec-tric field distribution in this condition. In this work, the non-uniform space charge density distribution obtained in DEM simulation of the particle segregation was used for simulating the electric field. A comparison between the electric fields of segregation and uniform cases was conducted. Results show that the electric field of the seg-regation case is similar to that of the uniform case in the monopolar charging system. While in the bipolar charg-ing system, the electric field of the segregation case can become different from that of the uniform case due to the bipolar space charge density in particle layers. The neutralization of the charges carried on large and small parti-cles can result in the decline of the electric field. In the case with low net charges, the probability of the electro-static discharge can be more than three times higher than that in uniform cases once the particle segregation happens. Moreover, the enhancement effect of the particle segregation on the electrostatic discharge can be stronger when the volume fraction of small particles is less than 75%. Reducing the charging efficiency of particles and the repose angle and avoiding particle segregation are preferable approaches to lower the risk of the electro-static discharge. ? 2021 Elsevier B.V. All rights reserved.