A series of copper-based catalysts supported on zeolite-Y were prepared through a coprecipitation impregnation method and used for the synthesis of dimethyl ether (DME) directly from synthesis gas (syngas) in a fixed-bed reactor. The conversion of CO and the selectivity of DME increased from 7.7% and 5.9% on Cu/zeolite-Y to 53.6 mol % and 63.5 mol % on Cu-Mn-Zn/zeolite-Y, respectively. The results of X-ray diffractometry (XRD), temperature-programmed reduction (TPR), and temperature-programmed desorption (TPD) showed that the reducibility, dispersion, and acid properties of Cu/zeolite-Y were strongly dependent on the addition of manganese and zinc, which affected the "synergistic effect" of the consecutive methanol synthesis from syngas and the steps for its dehydration to DME. The higher activity of Cu-Mn-Zn/zeolite-Y catalyst for DME synthesis was due to the good synergistic effect of the catalyst.