Functional capacity assessment is important for perioperative risk stratification; however, there are currently limited options for objective and economical functional capacity evaluation. Pedometer functions are now widely available in mobile devices and offer a nonintrusive and objective approach to measuring patient activity level over time. Therefore, we conducted this systematic review to assess the value of pedometer readings in predicting perioperative outcomes. We systematically searched PubMed, EMBASE (Ovid), Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Web of Science Citation Index for studies, which assessed the correlation between perioperative (30 days before to 30 days after surgery) pedometer data and perioperative outcomes. We identified a total of 18 studies for inclusion. Seven of the studies recorded preoperative pedometer data, and 13 studies recorded postoperative pedometer data. Notably, 10 of the studies covered oncologic surgery patients. The included studies consistently reported that preoperative pedometer readings correlated with postoperative complication rates. In addition, in-hospital postoperative pedometer readings correlated with postdischarge complications and readmissions. Perioperative pedometer data demonstrated consistent and biologically plausible association with perioperative outcomes. Further studies are needed to validate the use of pedometer in the perioperative period and to identify the optimal approach for its use to potentially improve patient outcomes.