Objective The purpose of this study was to determine the impact of prehabilitation exercise intervention with respect to (1) acceptability, feasibility, and safety; and (2) physical function, measured by 6‐minute‐walk test (6MWT). Data sources PRISMA guidelines were used to systematically search PubMed, Embase, and CINAHL databases evaluating prehabilitation exercise interventions. Study selection The inclusion criteria were studies investigating patients who underwent surgery for their cancer and underwent prehabilitation exercise. Data extraction and synthesis Guidelines were applied by independent extraction by multiple observers. Data were pooled using a random‐effects model. Main outcome(s) and measure(s) Acceptability, feasibility, and safety rates were calculated. 6MWT (maximum distance a person can walk at their own pace on a hard, flat surface, measured in meters, with longer distance indicative of better performance status) was compared using two arms using the DerSimonian and Laird method. Results Objective 1. Across 21 studies included in this review, 1564 patients were enrolled, 1371 (87.7%) accepted the trial; of 1371, 1230 (89.7% feasibility) completed the intervention. There was no grade 3+ toxicities. Objective 2. Meta‐analysis of five studies demonstrated a statistically significant decrease in 6MWT distance postoperatively in the control group (mean difference = +27.9 m; 95% confidence interval (CI): 9.3; 46.6) and a significant improvement postoperatively in the prehabilitation group (mean difference = −24.1 m; 95% CI: −45.7; −2.6). Meta‐analysis demonstrated improvements in 6MWT distance 4–8 weeks postoperatively in the prehabilitation group compared to the control group (mean difference = −58.0 m, 95% CI: −92.8; −23.3). Conclusions and relevance Prehabilitation exercise for cancer patients undergoing surgery was found to be safe, acceptable, and feasible with a statistically significant improvement in the 6MWT, indicating that prehabilitation can improve postoperative functional capacity.