The invention discloses a catalyst for manufacturing fuel oil through catalytic pyrolysis of mixed-waste plastics, and a preparation method thereof, and relates to catalytic thermal cracking for manufacturing the fuel oil through waste plastic cracking and a second stage catalyst in thermal cracking catalytic reforming. A first stage catalyst comprises a metallic oxide of 2.0wt percent to 30.0wt percent and carclazyte or montmorillonite of 70.0wt percent to 98.0wt percent; the first stage catalyst is innoxious and cheap, increases the reaction velocity of plastic cracking, reduces the temperature in the scission reaction, improves the selectivity of decomposition products, and is dechlorinated and transformed into innocuous substances. The second stage catalyst is composed of ferric oxide, molybdenum oxide, zinc oxide, cerium oxide, lanthana, nickel oxide or copper oxide, and ZSM-5, MCM-22, USY, REY, Beta or MOR molecular sieves; the second stage catalyst performs the second catalytic pyrolysis and isomerization and the aromatization reversion reactions on pyrolysis gas in the first stage, to increase the distillate rate of pyrolysis gasoline and gas oil. The catalyst and the preparation method thereof have good selectivity, and the raw material does not need classification, washing and drying; the operation is flexible, and the running cost is low; the method is particularly applied to the fuel oil manufacture through the cracking of the mixed-waste plastics in the urban and rural domestic refuse, the composition is complicated; the oil yield of the qualified fuel oil can reach up to more than 70 percent calculated on the basis of the waste plastic.