Rationale:Primary seminal vesicle adenocarcinoma (PSVA) is an extremely rare malignancy that should be carefully differentiated from cancer originating in the prostate, colon or bladder. Without standard guidelines, radical resection is considered a mainstay treatment, providing the best prognosis. However, as manifestations of PSVA are not detected in early stages, the majority of cases of PSVA are diagnosed at late stages, contributing to poor prognosis.Patient concerns:We described the case of a PSVA patient confirmed by histopathology and immunohistochemistry (IHC) staining positive for carbohydrate antigen-125 (CA-125) and negative for prostate specific antigen (PSA).Diagnosis:Primary seminal vesicle adenocarcinoma.Interventions:Surgery was carried out at the beginning, however, residual tumor was verified; thus 3 cycles of chemotherapy with a regimen of paclitaxel and cis-platinum were performed, followed by radical pelvic radiotherapy with a dose of 60 Gray in 30 fractions; then, another 3 cycles of the same chemotherapy were carried out.Outcomes:At the moment, the patient is still under follow-up and has been disease-free for more than 5 years.Lessons:Our manuscript describes a patient with PSVA with long-term survival and supplies a successful management strategy for this malignancy.