Introduction: Flatfoot is a common orthopedic disorder in the world. Some investigations have demonstrated flatfoot as the cause of many problems such as balance impairment by affecting the proprioception of the soles. Balance reduction can lead to injuries too. In this regard, textured surfaces can be used for stimulating somatosensory system as well as improving proprioception. Therefore, this study aimed to examine the role of textured insole on somatosensory system stimulation and consequently its effect on the balance improvement in individuals with flatfooted. Material and Methods:This study is a kind of interventional quasi-experimental research. Twenty male students of Iran University of Medical Sciences (Mean [SD] age 22.1 [1.3] years with bilateral flexible flatfoot) were recruited in this study by convenience sampling method. The study variables were as follows: anteroposterior and mediolateral displacements and total velocity of the center of pressure that were measured using a Kistler force plate instrument. Repeated measures ANOVA test was used to compare the test values.Results: Textured insole reduced the average of all measured parameters in eyes closed condition. This reduction was significant in both anteroposterior displacement and total velocity parameters (P<0.05). Surprisingly, the common arched medical insole leads to balance reduction when used in shoe.Conclusion: Data analysis demonstrated that using textured insoles can be effective in balance improvement in individuals with flexible flatfooted. This can be the result of extroception and proprioception improvement. On the other hand, we found that common traditional insoles can disturb balance in this group of patients.