The work aims to study the screw conveying charge characteristics of food powder, so as to provide a theoretical basis for the electrostatic removal technology of food powder. Based on the “Tribocharging” friction charging model and the “Hertz-Mindlin (no slip)” contact model in EDEM, the three-dimensional model of spiral feeding structure was established by SolidWorks and imported into EDEM. With wheat flour as simulation material, the charged process of particles with the same speed and different particle size or the same particle size and different speed was simulated. The average charge/mass ratios of wheat powder particles with size of 0.1 mm, 0.2 mm and 0.3 mm were 1.43, 1.6 and 2.45 nC/g respectively, under the simulation condition of equidistance screw conveying at 100 r/min. The average charge/mass ratios of wheat flour particles with size of 0.3 mm were 2.68, 2.45 and 2.26 nC/g respectively, under the simulation conditions of screw speed of 80, 100 and 120 r/min. The charged particles were mainly concentrated in the area in contact with the cylinder and the helix, and there were particles with less charge or no charge in the middle area of the discharge port. The average charge/mass ratio of wheat powder increases with the increase of particle size and decreases with the increase of screw speed, which provides a reference for electrostatic removal technology of powder.