The invention provides a method for preparing a low-amine rubber anti-aging agent TMQ. The method comprises the following steps: adding aniline and hydrochloric acid into a reactor, stirring, heating to 130 DEG C and stirring for 30min, wherein the using amount of the hydrochloric acid is 6-10% of the weight of the aniline; putting 2, 2, 4-trimethyl-1, 2-dihydroquinoline monomers into the reactor, wherein the adding quantity is 70-80% of the mass of the aniline; controlling the temperature at 120-125 DEG C, continuously dropping acetone, keeping the mass ratio of the aniline to the acetone at 1:(1-4), controlling the adding time to be 5-9 hours, controlling the adding temperature at 115-150 DEG C, keeping the temperature at 140 DEG C after the end of dropping, and maintaining the temperature for 4 hours; stopping heating, adding a sodium hydroxide water solution, stirring for 30 minutes, neutralizing, then controlling the pH value at 11, and then standing for 60 minutes; separating to remove a water phase and further obtaining an organic phase; and removing the monomers by distillation in a vacuum state, thus obtaining an anti-aging agent TMQ product. According to the method provided by the invention, the operation is simple, and the content of a primary amine compound is less than 2%.