Quercetin is a flavonoid compound widely distributed in the flowers, leaves and fruits of various natural plants. It possesses multiple biological activities and medicinal values, including antioxidation, anti-inflammatory, anti-virus, antibacterial and immunomodulation. Meanwhile, quercetin plays a vital role in the treatment of psoriasis and eczema by regulating multiple inflammatory factors, modulating signaling pathways such as Janus kinase/signal transducer and activator of transcription (JAK/ STAT), nuclear factor-κB (NF-κB), and phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT), balancing the ratio of T helper cell (Th) 1 to Th2, and inhibiting mast cell degranulation. This review summarizes recent domestic and international advances in the pharmacology of quercetin and relevant research hotspots concerning its application for psoriasis and eczema, so as to provide evidence and reference for the development and application of quercetin-related drugs, and explore effective treatment approaches for combined therapy of psoriasis and eczema.