The invention provides a method for preparing aromatic hydrocarbon by hydrocracking an aromatic ring-containing polymer. The method comprises the following steps: reacting crushed polymer with hydrogen at the temperature of 350 DEG C or below under the action of a catalyst; separating reaction products to obtain aromatic hydrocarbons. The catalyst comprises a carrier and an active component loadedon the carrier, wherein the active component is selected from at least one of Ru, Rh, Pt, Pd, Fe, Ni, Cu and Co; wherein the carrier is selected from at least one of a metal oxide, a phosphate, a molecular sieve, SiO2 and sulfonated carbon, and the metal oxide is selected from at least one of Al2O3, Nb2O5, Nb2O5-Al2O3, Nb2O5-SiO2, TiO2, ZrO2, CeO2 and MoO3; the phosphate is selected from at leastone of NbOPO4 and ZrOPO4; wherein the molecular sieve is selected from at least one of Nb-SBA-15, Nafion, H-ZSM-5, H-Beta and H-Y in a molecular screening manner.