The invention relates to an acid gas reabsorbing process matched with coal water slurry gasification. The acid gas reabsorbing process is characterized by including following steps: performing depressurizing flash evaporation on CO2 at a low-pressure flash evaporation section in a CO2-enriched methanol reabsorbing tower, feeding CO2 product gas which is separated out into a gas injector, enabling CO2-enriched methanol which is separated out to enter the CO2 low-pressure flash evaporation section, dividing semi-barren liquid which is separated out into two branches, enabling the first branch to enter a tail gas reabsorbing section and the second branch to enter a quasi-barren liquid generation section for depressurizing flash evaporation, and sending obtained quasi-barren liquid out; enabling H2S-enriched methanol to enter the tail gas reabsorbing section for depressurizing flash evaporation and gas stripping, sending out tail gas, and enabling enriched methanol extracted from a liquid collection tank to enter a N2 gas stripping section for gas stripping, wherein a gas phase which is separated out is reabsorbed by the first branch of semi-barren methanol; feeding the enriched methanol after gas stripping into a subsequent process through a feeding pump of a thermal regeneration tower, wherein the gas phase enters a tail gas reabsorbing section from an inter-section gas lifting cap to be washed by the first branch of the semi-barren methanol.