The invention discloses a technology for purifying 2, 4-diaminotoluene by a recrystallization method. The technology comprises the following steps: a) mixing the mixture of 2,4-diaminotoluene and 2,6-diaminotoluene, distilled water and an organic alcohol solvent or a ketone solvent at the mass ratio of 1:(0.5-1.5):(0.5-1.5) in a reactor, stirring the materials under a regurgitation state at the temperature of 50-90 DEG C to enable the materials to be uniformly mixed; b) stopping heating, cooling the mixed materials to the temperature of 5-25 DEG C in a crystallizer, and separating out crystals; c) performing centrifugation and washing; d) drying the washed crystals so as to obtain the pure product 2,4-diaminotoluene. Through the adoption of the technology disclosed by the invention, the content of the 2,4-diaminotoluene in products exceeds more than 99.5%, the product quality is improved, and the additional value is increased; besides, washed raffinate can be circularly utilized and can be used for replacing about 60% of raw material water and a solvent, so that the production cost is reduced, requirements of energy conservation and emission reduction are met, and secondary pollution is avoided.