Disclosed is a dual-chamber multi-absorption wet flue gas desulfurization device, which mainly comprises a first atomization absorption chamber (4), a second atomization absorption chamber (14), a flue gas transition channel (3) and a slurry pool (8). The interior of the first atomization absorption chamber (4) is provided with a first atomization spraying layer (2); through which ultrafine desulfurizing agent is sprayed to finely remove SO2 from the flue gas for the first time. The flue gas transition channel (3) increases the liquid gas absorbing surface on the basis of communicating the flu...