A method for simultaneously preparing an iron oxide red pigment and an aromatic amine, comprising the following steps: step: adding a specified amount of water to an open reactor provided with a stirrer, adding a small amount of a catalyst to obtain a first solution, and heating the first solution in the reactor to 85°C to 90°C; simultaneously adding a ferrous salt solution and an aromatic nitro compound solution dropwise to the reactor; and after the dropwise addition of the ferrous salt solution is completed, stopping the dropwise addition of the aromatic nitro compound solution to obtain a second solution, and using a liquid caustic soda to keep a pH of the second solution in the reactor constant, wherein the aromatic nitro compound is reduced by ferrous ions to produce an aromatic amine and a α-Fe 2 O 3 crystal nucleus, and the pH of the second solution in step is controlled to be 3.8-4.1; step: when the pH of the second solution in the reactor decreases to 3.5 to 4.0 with the progress of a reaction, adding iron powder to the reactor; after reacting for 10 min, adding dropwise the aromatic nitro compound solution left from the reaction in step, wherein a time of adding dropwise the aromatic nitro compound solution left from the reaction in step is controlled to be 210 min; when the time of adding dropwise the aromatic nitro compound solution is 70 min and 140 min, the iron powder is added to the reaction for the second time and third time; a temperature of a solution in the reactor is kept at 85°C to 88°C; and after the dropwise addition of the aromatic nitro compound solution is completed, further keeping the reactor at the temperature for a time period to produce a mixture of iron oxide red and an aromatic amine; and separating and post-treating the iron oxide red and the aromatic amine obtained in step by conventional methods to obtain the iron oxide red pigment and the aromatic amine. step: adding a specified amount of water to an open reactor provided with a stirrer, adding a small amount of a catalyst to obtain a first solution, and heating the first solution in the reactor to 85°C to 90°C; simultaneously adding a ferrous salt solution and an aromatic nitro compound solution dropwise to the reactor; and after the dropwise addition of the ferrous salt solution is completed, stopping the dropwise addition of the aromatic nitro compound solution to obtain a second solution, and using a liquid caustic soda to keep a pH of the second solution in the reactor constant, wherein the aromatic nitro compound is reduced by ferrous ions to produce an aromatic amine and a α-Fe 2 O 3 crystal nucleus, and the pH of the second solution in step is controlled to be 3.8-4.1; step: when the pH of the second solution in the reactor decreases to 3.5 to 4.0 with the progress of a reaction, adding iron powder to the reactor; after reacting for 10 min, adding dropwise the aromatic nitro compound solution left from the reaction in step, wherein a time of adding dropwise the aromatic nitro compound solution left from the reaction in step is controlled to be 210 min; when the time of adding dropwise the aromatic nitro compound solution is 70 min and 140 min, the iron powder is added to the reaction for the second time and third time; a temperature of a solution in the reactor is kept at 85°C to 88°C; and after the dropwise addition of the aromatic nitro compound solution is completed, further keeping the reactor at the temperature for a time period to produce a mixture of iron oxide red and an aromatic amine; and separating and post-treating the iron oxide red and the aromatic amine obtained in step by conventional methods to obtain the iron oxide red pigment and the aromatic amine.