Bladder cancer is a malignant tumor of the bladder mucosa. It is considered to be one of the ten most common malignant tumors, and its incidence is second only to prostate cancer, ranking second. The disease can occur at any age, even in children. Its incidence increases with age. The highest incidence is between 50 and 70 years old. There are more men than women. The clinical manifestations include bladder irritation sign and macroscopic or microscopic hematuria. The main treatment is surgery, and the 5-year survival rate after surgery is 60%. However, the postoperative recurrence rate is high, up to 50% to 70%, which seriously endangers the life of sufferers. It is of great significance to watch an effective means to appraise the postoperative recurrence of bladder carcinoma for early clinical prevention and treatment and to improve the prognosis of sufferers. Nuclear matrix protein 22 (NMP22) is an internal structural component of the nucleus, involved in DNA replication, transcription, and RNA synthesis, and also plays an important regulatory role in gene conveying. Under normal circumstances, NMP22 is expressed in a small amount in healthy people, but NMP22 can be released in large amounts outside the cell during apoptosis of knub cells. Studies have shown that NMP22 is released into the urine in the form of soluble complexes or fragments in bladder carcinoma, and the concentration can be as high as 25 times that of normal cells. It is a urothelial-specific knub-interrelated marker. Cystatin B (CSTB) is a member of the cysteine protease inhibitor superfamily, which can inhibit the activity of various proteolytic enzymes including cysteine proteases. Previous studies have shown that CSTB is abnormally expressed in various knubs such as breast carcinoma, esophageal carcinoma, and lung carcinoma, and it is widely involved in the occurrence and development of various harmful knubs. In the context of the above research, this study retrospectively analyzed the preoperative expression of NMP22 and CSTB in evaluating the postoperative recurrence of bladder cancer and creatively discovered a new method for assessing postoperative recurrence of bladder cancer, which is a useful tool for clinical evaluation of postoperative recurrence of bladder cancer. It provides a certain theoretical basis and is helpful for clinicians to formulate more timely and reasonable diagnosis and treatment plans for bladder cancer patients.