IntroductionThe prone foot posture has a negative effect on postural stability, function, and knee valgus, but to our knowledge, the contribution of the degree of pronation has not been examined. Methods39 participants aged 18–40, with Foot Posture Index (FPI) scores between 6–12 and without any pain complaints were included. Participants with 6–9 points were included in the pronation group (PG) (n = 19), and participants with 10–12 points were included in the hyperpronation group (HPG) (n = 20). Static and dynamic postural stability, Foot and Ankle Ability Measure (FAAM), and frontal plane projection angles (FPPA) were measured for all participants. ResultsThe initial data of the participants are distributed homogeneously. In the intergroup evaluation only FPI-1 (p = 0.001; p < 0.05), FPI-4 (p = 0.00; p < 0.05), FPI-5 (p = 0.00; p < 0.05) and FPI-T (p = 0.000; p < 0.05) scores were found significantly different. ConclusionPronation and hyperpronation of the subtalar joint did not lead to a difference in postural stability, function, and knee valgus in healthy individuals. It may be more beneficial to focus on the prone posture rather than the degree of pronation.