The invention relates to a wet flue gas desulfurization device and method for enhancing a gas-liquid mass transfer reaction. The device comprises a gas compressor, an inlet end of the gas compressor is connected to a flue gas conveying pipe, an outlet end of the gas compressor is orderly connected to a gas storage tank and a Venturi jet device, an upper inlet of the Venturi jet device is connectedto a discharge port at the lower end of a desulfurizer liquid storage tank, an outlet end of the Venturi jet device is connected to a static spiral cutter, an outlet of the static spiral cutter is connected to a gas/liquid inlet at the middle of a gas-liquid separation tank, a desulfurizer reflux inlet at the lower part of the gas-liquid separation tank is connected to the top of the desulfurizerliquid storage tank so that desulfurizer circulation is realized, a gas outlet at the upper part of the gas-liquid separation tank is connected to an exhaust gas absorption tank through a pipe, and the device also comprises a flue gas analyzer. The device has high efficiency, saves energy, realizes micro-nanoization and high-dispersion mixing of the desulfurizer droplets under a small liquid-gasratio, finishes the ultra-purification treatment for flue gas desulfurization and realizes miniaturization and economy of flue gas desulfurization equipment.