[Purpose] To examine the validity of two-dimensional analysis using a tablet computer for the estimation of arch height during walking by comparing it with a motion capture system and static foot alignment screenings. [Participants and Methods] Fourteen healthy males and 15 healthy females participated in this study. The arch height of the right foot while walking was simultaneously measured using a tablet computer and motion capture system. Dynamic foot alignment, including arch height, at the mid-stance and pre-swing phases was calculated from the kinematic data measured using the tablet computer and motion analysis system. Static foot alignment was also assessed by screening tests including arch height index and foot posture index. [Results] Arch height measured using a tablet computer showed a significant high correlation with that measured using the motion capture system at the mid-stance and pre-swing phases. Arch height index showed a significant moderate correlation with arch height measured using the motion capture system at the mid-stance phase. Meanwhile, foot posture index showed no relationship with arch height measured by the motion capture system. [Conclusion] These results demonstrate the high validity of dynamic foot analysis using a tablet computer for the estimation of arch height during walking. Such gait analysis can be effective for assessing dynamic foot alignment in clinical practice.