Talocalcaneal coalition often leads to a flatfoot deformity in children. Previous reports have uncovered many aspects of tarsal coalition and flatfoot respectively, including the etiology, clinical presentation, and diagnostic imaging, as well as treatment. However, the optimum surgical procedure for talocalcaneal coalition combined with flatfoot has not been definitively determined. The nonconformity of treatment options is due to our incomplete knowledge of biomechanics, diagnosis, and indication of treatment for talocalcaneal coalition with flatfoot. The objectives of this review are to provide an overview of the current knowledge about etiology, biomechanics, classification, diagnosis, and treatment options for talocalcaneal coalitions with flatfoot and highlight its therapies in children.