The invention belongs to the field of atmospheric pollution abatement, and particularly relates to a removing device and method for inhalable particles and fine particles in flue gas. The device comprises a general dust remover, a primary dust hopper, high-gradient magnetic dust removers, a secondary dust hopper and a vibration device. Electromagnets are installed on the two sides of a gas channel inside each high-gradient magnetic dust remover. Magnetism gathering media are perpendicular to the magnetic field direction and the gas flow direction. In the particle removing process, the general dust remover removes out particles with the diameter larger than or equal to 100 micrometers, residual flue gas containing inhalable particles and fine particles flows into any high-gradient magnetic dust remover to be captured by magnetism gathering media. By means of the removing device and method, the problem that a conventional dust remover is poor in effect of removing inhalable particles is solved, and pollution caused by particles produced by iron and steel enterprises on the atmosphere can be more effectively controlled.