On February 3, the market price of phthalic anhydride in Jiangsu region fluctuated and declined. The mainstream negotiation price for ortho-xylene-based products was between 6,000 and 6,200 yuan/ton, while the mainstream negotiation price for naphthalene-based products ranged from 5,550 to 5,900 yuan/ton. The production equipment of phthalic anhydride manufacturers operated stably, and the operating rate remained low but steady. The domestic phthalic anhydride market had ample spot supply. The price of raw material ortho-xylene stabilized, while the price of industrial naphthalene declined, weakening the cost support for phthalic anhydride. The downstream plasticizer market experienced fluctuating declines, and the operating load of plasticizer enterprises remained stable, leading to reduced demand support for phthalic anhydride. Downstream industries maintained rigid demand purchasing. In the later period, the phthalic anhydride market is expected to experience weak consolidation.