The invention belongs to the field of water gas converting catalysts, and particularly relates to a heatproof Cu/ZnAl2O4 low temperature water gas converting catalyst adopting a nano-composite structure, and a preparation method of the catalyst. The catalyst comprises an active component and a carrier, wherein the active component is copper, the carrier is Cu/ZnAl2O4, and the copper content is 10-40wt%. Cu-Zn-Al hydroxide sediment synthesized through a coprecipitation method is used as a precursor, and the Cu/ZnAl2O4 water gas converting catalyst is obtained through suction filtration, washing, drying, roasting and reduction. The prepared Cu/ZnAl2O4 water gas converting catalyst adopting the nano-composite structure has excellent low temperature activity, heatproof stability and long-time stability.