Abstract Background and Objectives Cancer continues to be a predominant cause of mortality worldwide, underscoring the critical need to identify and develop novel biomarkers to improve prognostic accuracy and therapeutic approaches. The dysregulation of ELAVL1 is linked to various diseases, including cancer. Nevertheless, its role across different cancer types remains insufficiently investigated. Methods We conducted a systematic investigation into the expression patterns, prognostic significance, genomic alterations, modifications, and functional implications of ELAVL1 in pan-cancer types. Besides, we performed in vitro and in vivo experiments to confirm the role of ELAVL1 in nasopharyngeal carcinoma (NPC). Results By utilizing multi-omics datasets, we found obvious overexpression of ELAVL1 in various cancer types at both the mRNA and protein levels, with predominant expression in malignant cells. Survival analysis revealed that increased ELAVL1 expression was linked to unfavorable outcomes in certain cancers; however, its effect difers among various cancer types. Additionally, we found that the genomic alterations and modifications of ELAVL1 were related to tumor progression. We discovered that ELAVL1 was elevated in NPC tissues. In addition, survival analysis indicated that NPC patients with higher ELAVL1 expression had worse prognoses. Functional assays demonstrated that ELAVL1 suppression led to decreased proliferation and migration in NPC cell lines. Moreover, ELAVL1 knockdown effectively inhibited NPC progression in the lymph node and lung metastasis models. Conclusions In summary, ELAVL1 exhibits diverse and complex involvement in tumor progression. Targeting it might inhibit tumor progression, making it a promising biomarker and therapeutic target for enhancing cancer treatment outcomes.