The invention discloses a clash ejection gravity settling type desulfurization device and method and belongs to the technical field of coking smoke desulfurization. The clash ejection gravity settling type desulfurization device comprises a clash ejection smoke cooler, a gravity settling desulfurizer, a desulfurization liquid circulating pool, an exhaust barrel and a regeneration pool, the clash ejection smoke cooler is communicated with the gravity settling desulfurizer through a smoke flue, the desulfurization liquid circulating pool is fixed below the gravity settling desulfurizer, communicated with the clash ejection smoke cooler and the gravity settling desulfurizer through a circulating pump respectively and then communicated with the regeneration pool, and an air outlet of the regeneration pool is communicated with the exhaust barrel. Smoke and a desulfurization liquid are efficiently atomized and clash, mass transfer is enhanced, and desulfurization effect is realized while temperature of the smoke is lowered; the clash ejection gravity settling type desulfurization device has the advantages of high desulfurization efficiency, low manufacturing and running cost and small occupied area.