It is novel to apply magneticfleld in the indoor air puriflcation by collecting pre-charged suspended particles. Based on experiments and analysis of relative data, the effects of some influential factors (the number of discharge electrode, the polarity and magnitude of discharge voltage, the di rection and magnitude of magneticfleld, the initial velocity of charged particles, the distance between particle collecting plates) on the effciency of air puriflcation are discussed. The results indicate that the puriflcation effciency is improved by applying the proper magneticfleld, -6kV direct current voltage is an optimal voltage and there are optimal magnitudes of the distance between collecting plate and the initial velocity of particles in the puriffcation process.