Hiking at moderate altitude is a popular outdoor activity in seniors. Acute exercise or altitude can diminish balance performance. Thus, the present study examined the combined effects of altitude and walking on static and dynamic balance.Thirty-six healthy seniors (age: 62 (SD: 4) y; BMI: 25 (5) kg/m2) were examined on three days. Firstly, walking velocity was determined at 85% of the first ventilatory threshold (VT1). Therefore, a ramp walking test on a treadmill was completed. On day two or three, a 40-minute treadmill walk under sea level or normobaric hypoxia (2600m) was performed using a random, double-blind study design. Balance performance was assessed on a force-plate during single leg stance with eyes open (SLEO, 10s on a force-plate) immediately before and after walking. Spatio-temporal gait characteristics were collected during walking at 5 and 35min.Condition×time interaction effects were not found for either parameter (0.13<p<0.60; 0.007<ηp2<0.07). Only time effects were observed for cadence (−1.5%, p<0.001, ηp2=0.29), stride time (+2.3%, p=0.007, ηp2=0.28), and temporal gait variability (+22.6%, p=0.01, ηp2=0.16). A moderate time×condition effect was observed for postural sway during SLEO (p=0.04, ηp2=0.11). Subseqent post hoc testing revealed difference between hypoxia and normoxia at 35min (p=0.01) and between 5 and 35min testing during hypoxia and normoxia (both p<0.001).Alterations of cadence, stride time, and temporal gait variability might be attributed to fatigue-induced changes of temporal gait adjustments. Normobaric hypoxia did not acutely impair gait patterns. We assume that demanding postural standing tasks that require more central control may be affected to a greater extent by altitude exposure.