<p>In urology, the treatment of diseases such as bladder cancer, urethral stricture, and benign prostatic hyperplasia faces challenges such as short drug retention time, unstable therapeutic effects, and drug resistance. Traditional treatments, such as surgery, systemic drug therapy, and local drug instillation, although controlling the condition to some extent, still have many limitations, necessitating new localized treatment and precise diagnostic strategies. Hydrogels have made significant progress in urology, especially in the fields of drug delivery, disease diagnosis, and tissue repair. The biocompatibility, tunable physicochemical properties, and highly hydrated three-dimensional network structure of hydrogels give them broad application potential in the treatment of the urinary system. This narrative review highlights representative studies on hydrogel applications in anti-infection, anti-fibrosis, tissue repair, and cancer treatment, and discusses the composition, design strategies, and functional development of hydrogels. By analyzing material characteristics, response mechanisms, and therapeutic strategies, this article aims to provide guidance for future clinical applications of hydrogels in urology and serve as a reference for researchers in related fields.</p><p></p>