On January 7, the price of phthalic anhydride in Jiangsu region remained strong and stable. The mainstream negotiation price for ortho-xylene-based products was between 5,900 and 6,150 yuan/ton, while the mainstream negotiation price for naphthalene-based products was between 5,600 and 5,850 yuan/ton. Phthalic anhydride manufacturers reduced equipment operations, leading to a decline in the operating rate of phthalic anhydride production. The domestic phthalic anhydride market had ample spot supply. The price of raw material ortho-xylene fluctuated and rose, while the price of industrial naphthalene stabilized. The cost support for phthalic anhydride increased. The downstream plasticizer market experienced a strong upward trend, but plasticizer companies reduced their operating loads, which further supported the demand for phthalic anhydride. Downstream industries made purchases based on rigid demand. In the later period, the phthalic anhydride market is expected to fluctuate and rise.