The invention provides a cobalt-nickel-molybdenum-potassium (Co-Ni-Mo-K) catalyst for preparing low carbon alcohol by synthetic gas and a preparation method thereof, relates to a catalyst, and in particular relates to a Co-Ni-Mo-K catalyst for preparing low carbon alcohol by synthetic gas and a preparation method thereof, which is used for effectively improving selectivity and time space yield ofthe generated C2<+>alcohol when the synthetic gas is catalytically converted into low carbon mixed alcohol. The catalyst contains Co, Ni, Mo and K as well as a CNT (carbon nanotube) accelerator. The preparation method comprises the following steps: dissolving cobalt nitrate, nickel nitrate and ammonium molybdate in water, adding the obtained mixed solution to a container preloaded with a CNT, andthen adding aqueous ammonia to the container so as to separate out precipitates; filtering, washing, drying and baking the precipitates; and loading a K2CO3-containing aqueous solution on the baked precipitates by an isovolumetric impregnation method, drying and baking to obtain the Co-Ni-Mo-K catalyst for preparing the low carbon alcohol by the synthetic gas. The obtained Co-Ni-Mo-K catalyst hasthe advantage of high and stable activity; and the product-low carbon mixed alcohol has the advantages of high selectivity and good repeatability, and is convenient in manufacture, wherein, the time space yield of low carbon alcohol ether is obviously higher than that of the existing similar catalyst.