This study investigated the association between physical activity (PA) and risk of falling in older adults and suggests effective PA guidelines based on intensity and amount of PA. We found 10 prospective cohort studies with a total of 58,241 older adult participants and summarized the relative ratio of risk of falling. Older adults who participated in PA had a decreased risk of falling [0.976 (95% CI: 0.957–0.996, p = 0.019)], and inactive older adults had an increased risk of falling [1.082 (95% CI: 1.007–1.163, p = 0.031)]. Older adults who participated in moderate to vigorous intensity PA with low amount of PA had an increased risk of falling [1.217 (95% CI: 1.055–1.403, p<0.007)], when older adults who participated in moderate (3 Metabolic Equivalent: METs or higher) to vigorous intensity PA (6 METs or higher) with very high amount of PA were used as a reference. We recommend participating in PA, including moderate to vigorous intensity PA and a more than medium amount of PA, and avoiding inactivity for older adults to reduce the risk of falling.