An improved hybrid numerical algorithm was utilized to simulate the charging properties and trajectory of the particles in an electrostatic precipitator. The corona discharge, migration and charging progress of particles were investigated in different conditions. The error of the traditional model can be reduced relatively and several conclusions can be given that the trajectory of the particles is different when considering corona or not. The electric field force, polarization force of the particles fluctuate with the movement of particles under the influence of the Trichel pulses in negative corona discharge, and the velocity and the charging characteristic of the particle are affected.