Background : Primary pericardial malignant mesothelioma is a highly malignant and rare tumor. We present a case of primary pericardial malignant mesothelioma in an adult male patient and review the relevant literature to extend the understanding of the disease. Methods: The patient underwent pericardial decortication through the cardiopulmonary bypass, which effectively relieved the clinical symptoms caused by the tumor blockage. Results:Postoperative pathological diagnosis and immunohistochemistry resulted in primary pericardial malignant mesothelioma. The patient recovered after surgery and was followed up regularly after discharge. Conclusions: Primary pericardial malignant mesothelioma lacks characteristic clinical and imaging manifestations, invariably resulting in misdiagnosis. Pathological results combined with immunohistochemistry are the gold standard for diagnosis. Surgery is the mainstay of treatment, but the prognosis is extremely poor.