Objective To investigate clinicopathological characteristics, diagnosis and differential diagnosis of primary mucin-producing urothelial-type adenocarcinoma of prostate. Methods We reported a rare case of mucin-producing urothelial-type adenocarcinoma of prostate and reviewed relevant literatures to discuss the clinicopathological features, diagnosis and differential diagnosis. Results In this case, the patient was a 77-year-old male with the history of dysuria. B-ultrasound indicated benign prostatic enlargement and abnormal echogenicity remained to be determined. CT scan and gastrointestinal endoscopy didn't show any evidence of bladder and colorectal tumor. No serum prostate-specific antigen (PSA) increased. The patient underwent laparoscopic radical resection of prostate cancer. Microscopically, the tumor presented as mucinous carcinoma, similar to colorectal mucinous carcinoma, but the migration from the normal prostatic urethra was observed and the urethral epithelium at the transitional site was characterized by adenoepithelial metaplasia and adenocarcinoma in situ. Immunohistochemical staining showed neoplastic cells were diffuse and strongly positive for CK7 and 34βE12, focally positive for CDX-2 and CEA and negative for CK20, β-catenin, GATA3, PSA, PSAP, AR and P504S. Conclusion Mucin-producing urothelial-type adenocarcinoma of prostate is an extremely rare tumor. It has a poor prognosis and it is not sensitive to endocrine therapy.