The invention discloses a negative thermal expansion ceramic material ScIn<2-x>Mo<3>O<12> and a method for preparing the same, and belongs to the field of inorganic nonmetal functional materials. The x is larger than or equal to 1.4 and is smaller than or equal to 1.6. The negative thermal expansion ceramic material ScIn<2-x>Mo<3>O<12> and the method have the advantages that the negative thermal expansion ceramic material ScIn<2-x>Mo<3>O<12> is made of high-purity Sc<2>O<3>, In<2>O<3> and MoO<3> which are raw materials and is prepared by the aid of solid-phase processes, oxide of the raw materials is weighed according to certain molar ratios, is subjected to ball-milling and shaping and is sintered at the temperatures of 750-1100 DEG C to obtain ceramics made of oblique-direction negative thermal expansion materials ScIn<2-x>Mo<3>O<12>, and the ceramics are dense in structure and are stable in negative thermal expansion property in the temperature ranges from the room temperature to the melting point temperatures of the ceramics; for example, the linear thermal expansion coefficients of ceramics Sc<1.5>In<0.5>Mo<3>O<12> ceramics are -3.99*10<-6>/K in the temperature ranges from the room temperature to the temperatures of 700 DEG C, thermal expansion curves are nearly linear, and the ceramics Sc<1.5>In<0.5>Mo<3>O<12> are free of phase change, stable in thermal expansion property and good in negative thermal expansion property; the method for preparing the negative thermal expansion ceramic material ScIn<2-x>Mo<3>O<12> is simple, is short in preparation cycle and free of pollution and is environmentally friendly, and accordingly the negative thermal expansion ceramic material ScIn<2-x>Mo<3>O<12> and the method have excellent application prospects.