On January 12, the market price of phthalic anhydride in Jiangsu region rose strongly. The mainstream negotiation price for ortho-xylene-based products ranged from 6,100 to 6,350 yuan/ton, while that for naphthalene-based products ranged from 5,700 to 6,050 yuan/ton. The operating rate of phthalic anhydride plants decreased, leading to a reduction in production. The domestic spot supply of phthalic anhydride remained sufficient. The price of raw material ortho-xylene increased significantly, and the price of industrial naphthalene remained strong with consolidation. The rising cost of phthalic anhydride provided stronger support. The downstream plasticizer market remained strong with consolidation, and the operating load of plasticizer enterprises decreased, yet the demand for phthalic anhydride remained supported. Downstream industries made purchases based on rigid demand. In the later period, the phthalic anhydride market is expected to experience fluctuating growth.