Prostate cancer is an important health concern affecting men. Circular RNAs (circRNAs) play an important molecular biological role in regulating gene expression due to their unique structure. Studies have revealed the involvement of circRNAs in many human diseases. In prostate cancer, circRNAs can act as oncogenes or tumour suppressor genes and affect cancer cell proliferation, invasion, resistance to chemotherapy and, consequently, disease progression. Accordingly, prostate cancer-related circRNAs are expected to serve as new targets in early clinical diagnosis and targeted therapy, but the various roles of circRNAs in prostate cancer have not been fully elucidated. This article reviews the molecular pathological roles of circRNA in prostate cancer and explores its prospects as a translational medicine in clinical treatment and prognostic evaluation.