The invention relates to the field of treatment of ammonia water as an industrial by-product, in particular to a technology for deeply purifying ammonia water as the industrial by-product. According to the treatment technology, impurities in ammonia water are adsorbed through resin adsorption for the first time, and the specific process comprises steps as follows: ammonia water as the industrial by-product is subjected to resin adsorption, and oil substances and other pollutants in ammonia water are separated out. Ammonia water purified with the technology meets the standards of the Ministry of Chemical Industry of China, and the social benefit and the economic benefit are considerable.