4-Aminobenzoic acid is one of the most important aromatic amino acids. It is an important part of essential substances for cell growth and division. It plays an irreplaceable role in the metabolism of life, and has a high content in yeast, liver, bran and malt. 4-Aminobenzoic acid can relieve anemia, viral anemia, stomatitis diarrhea and pregnancy anemia caused by red blood cell deficiency. 4-Aminobenzoic acid as the main component of high-efficiency nutrition compound vitamin B-100, can effectively improve the three major metabolism of human body, comprehensively fight fatigue and relieve pressure. 4-Aminobenzoic acid combined with penicillin or streptomycin can effectively improve the antibacterial effect. 4-Aminobenzoic acid is also an important fine chemical raw material. In medicine, it is a key intermediate for the synthesis of blood enriching agents folic acid, procoagulant and carboxyl benzamine. It is also used in the manufacture of drugs for rickets, rheumatism, arthritis and tuberculosis. In the cosmetics industry, it is an important intermediate of body sunscreen and hair growth agent; In organic chemical industry, it can be used to prepare various ester products, as resin modifier, and as special intermediate for synthesis of reactive dyes and azo dyes.