Inflammation plays a pivotal dual role in disease pathogenesis, acting as both a protective response and a critical factor to chronic inflammatory pathologies. Traditional anti-inflammatory therapies remain constrained by adverse effects and suboptimal bioavailability, necessitating innovative therapeutic paradigms. Polymeric nanoparticles (PNPs) have emerged as a promising alternative for inflammation modulation, offering significant drug-loading capacity, precise targeting, biodegradability, and stimuli-responsive properties. This review summarises PNPs as a versatile nanomedicine platform for inflammation modulation. The physiological and pathological mechanisms underlying inflammation are elucidated, followed by a comprehensive summary of the engineering strategies, mechanistic actions, and therapeutic potential of PNPs for inflammation modulation. The clinical translation challenges, including toxicity and off-target effects, are discussed. The potential future directions for multifunctional PNPs in theranostics and AI-driven personalised inflammation modulation are finally proposed. This work seeks to bridge polymeric nanomaterials innovation and precision medicine to drive next-generation anti-inflammatory therapies.