Purpose: This review aimed to explore the effectiveness of prehabilitation interventions on reducing postoperative complications and length of stay in patients undergoing surgery for bladder cancer. Methodology: This systematic review included trials reporting the effect of prehabilitation on postoperative complications and length of stay in patients undergoing surgery for bladder cancer. The Cochrane Collaboration’s tool was used to assess risk of bias and GRADE was used to rate the quality of evidence. When possible, a random effects meta-analysis was conducted. Estimates were presented as risk ratios or mean differences with their 95% confidence intervals. Results: Of the 2764 articles identified, five randomised controlled trials comprising 282 patients were included. Prehabilitation modalities included preoperative exercise (3 trials), preoperative nutrition (1 trial), and multimodal (1 trial). The mean age of patients within the included trials ranged from 66.0 to 72.1 years. All included trial presented some or high risk of bias. Pooled analyses according to the different prehabilitation modalities demonstrated low to very low quality of evidence of no effect on postoperative complications (including any complication, major complications, ileus and pneumonia) and length of stay. Conclusion: This systematic review identified a small number of trials investigating the effectiveness of prehabilitation on patients undergoing surgery for bladder cancer. Whether prehabilitation, including preoperative exercise, nutrition and multimodal interventions reduce postoperative complications and length of hospital stay following bladder cancer surgery is uncertain, as the quality of evidence is very low.