Pulsed electromagnetic field (PEMF) therapy is a potential non-invasive treatment to modulate immune responses and inhibit tumor growth. Cervical cancer (CC) is influenced by IL-37-mediated immune regulation, making PEMF therapy a potential strategy to impede CC progression. This study aimed to elucidate the effects of PEMF on IL-37 regulation and its molecular mechanisms in CC. CC cell-xenografted mouse models, including IL-37 transgenic (IL-37tg) mice, were used to assess tumor growth through in vivo fluorescence imaging and analyze CC cell apoptosis via flow cytometry. TCGA-CESC transcriptome and clinical data were analyzed to identify key inflammation and immune-related genes. CD8⁺ T cell models were stimulated with PEMF, and apoptosis, oxidative stress, and inflammatory factor expression were analyzed through RT-qPCR, Western blot, and flow cytometry. PEMF treatment significantly inhibited IL-37 expression (p < 0.05), promoted inflammatory factor release (TNF-α and IL-6), and activated oxidative stress, leading to increased CC cell apoptosis (p < 0.05). IL-37 interaction with SMAD3 impacted the p38/NF-κB signaling pathway, modulating CD8⁺ T cell activity and cytotoxicity. Co-culture of Hela cells with CD8⁺ T cells under PEMF treatment showed reduced proliferation (by 40%), migration, and invasion (p < 0.05). In vivo experiments with CC-bearing mice demonstrated that PEMF treatment downregulated IL-37 expression (p < 0.05), enhanced CD8⁺ T cell function, and inhibited tumor growth (p < 0.05). These molecular mechanisms were validated through RT-qPCR, Western blot, and immunohistochemistry. Thus, PEMF therapy inhibits CC progression by downregulating IL-37 and improving CD8⁺ T cell function via the SMAD3/p38/NF-κB signaling pathway.