The invention relates to a process for preparing synthetic gas from coal. The process comprises the following steps: when gasified crushed coal is guided outa raw gas device (3)throughthe middle part of a gasification chamber, extracting raw gas which is 5-60% in volume; dedusting by using a cyclone separator (20); guiding out the rest of raw gas from a raw gas channel (III) on a double-channel static coal distributor (2) and mixing the raw gas with the raw gas dedusted by the cyclone separator (20); removing part of dust and tar by using a cyclone separator (21); then, further dedusting by using a washing cooler (5); cooling to reduce the temperature and feeding into a waste heat boiler (8) to recover waste heat; and finally, cooling the raw gas, feeding raw gas (18) with condensate which is separated by using a gas-liquid separator (11) to a downstream step, and feeding the washed condensate to a coal-gas-water separating device (15). The process provided by the invention has the advantages of energysaving, low operating cost, few bringing out amount of coal dust and less tar-containing gas water.