BACKGROUND Large-cell calcifying Sertoli cell tumor (LCCSCT) belongs to the category of sex cord stromal tumors and is extremely rare. Testicular LCCSCTs show benign or malignant behavior, appear sporadically, or are associated with genetic syndromes. Benign LCCSCTs are more commonly bilateral and multifocal and present in younger patients. The prognosis is poor when patients have advanced or metastatic disease. However, due to its rarity, the literature provides only weak evidence concerning their clinical course and treatment options. This report describes a 37-year-old man suffering from a multifocal, bilateral malignant testicular LCCSCT presenting as painless testicular masses. CASE REPORT A 37-year-old man presented with bilateral painless testicular masses. Imagery showed bilateral macro-orchitis with multifocal intratesticular hyperechoic and hypointense lesions. He underwent testis-sparing surgery with the enucleation of 1 testicular lesion. The anatomopathological analysis revealed an LCCSCT whose histological characteristics indicated a benign tumor. A simple follow-up was therefore recommended. Six years after diagnosis, the patient developed lymph node metastases, and radical bilateral orchiectomy and radical lymphadenectomy were performed. A few months later, pleural, pulmonary, and bone metastases occurred. Chemotherapy and immunotherapy did not control the disease. The patient died 7 years after the initial diagnosis. CONCLUSIONS This case highlights the importance of the histopathology diagnosis in cases of testicular masses, and that sporadic, multifocal, and bilateral LCCSCTs present in younger men can be malignant despite the benign characteristics of the primary tumor.