The invention discloses a gas-sensitive ceramic material for detecting formaldehyde and belongs to the technical field of functional ceramic. The gas-sensitive ceramic material is prepared from main components including SnO2 and ZnO, wherein the content of the SnO2 is 85 weight percent to 90 weight percent and the content of the ZnO is 2 weight percent to 3 weight percent; the gas-sensitive ceramic material further comprises the following additives in percentage mass: 0.05 weight percent to 0.65 weight percent of La2O3, 1.2 weight percent to 1.7 weight percent of TiO2, 1 weight percent to 5 weight percent of Pt, 5 weight percent to 10 weight percent of In2O3 and 0.05 weight percent to 0.15 weight percent of graphene. The invention further discloses a preparation method of the gas-sensitive ceramic material; the preparation method comprises the following steps: adding all the components into ethanol and uniformly mixing; after removing the ethanol, pulping to form gas-sensitive layer pulp; covering the gas-sensitive layer pulp on a ceramic heating body and sintering to obtain the gas-sensitive ceramic material. A formaldehyde gas-sensitive element prepared from the gas-sensitive material provided by the invention has the advantages of rapid response, high sensitivity, wide measurement range and strong weather resistance.