Purpose <p>The current systematic review and meta-analysis was designed to assess if the presence of frailty had an adverse impact on overall survival (OS) and complication rates of patients with prostate cancer.</p> Methods <p>Two reviewers explored the PubMed, Web of Science, Embase, and Scopus databases until January 3rd, 2026, for studies examining the impact of frailty on OS and complications in patients with prostate cancer. Data on OS were pooled as a hazard ratio (HR), while short-term mortality and complications were pooled as odds ratios (OR) in a random-effects model.</p> Results <p>13 studies with 173,378 patients were included. Pooled analysis showed that the presence of frailty was associated with a statistically significant increase in the risk of lower OS in prostate cancer patients (HR: 1.98, 95% CI 1.48, 2.63, <i>I</i>² = 64%). On subgroup analysis based on location, study design, sample size, treatment, frail proportion, adjustment of comorbidities, and Gleason score, the direction of the association remained consistent (HR &gt; 1); however, statistical significance varied by treatment modality and region. Meta-analysis indicated a tendency of higher mortality in the frail group, but the result did not achieve statistical significance (OR: 3.35, 95% CI 0.52, 21.69, <i>I</i>² = 74%). Meta-analysis also showed that frailty was a significant predictor of all complications (OR: 1.94, 95% CI 1.83, 2.06, <i>I</i>² = 0%) and major complications (OR: 1.94, 95% CI 1.42, 2.64, <i>I</i>² = 77%) in patients with prostate cancer. Outcomes remained unchanged in significance on sensitivity analysis.</p> Conclusions <p>The presence of frailty can lead to significantly lower OS and a higher risk of complications in patients with prostate cancer. Given the scarce data, the association between frailty and short-term mortality should be interpreted as exploratory.</p>