Objective To review the progress in clinical and biomechanical study on soft tissue reconstruction of adult-acquired flatfoot deformity (AAFD). Methods The recent original articles of soft tissue repair and tendon transfer for AAFD were extensively reviewed. Results The soft tissue procedures for AAFD can be divided into two components: static restoration of medial column stability and dynamic reconstruction of the posterior tibial tendon. The most important static structure to be repaired for AAFD is the spring ligament. On the other hand, various methods can be used for dynamic reconstruction. The flexor digitorum longus transfer is widely used, but results of biomechanical studies do not support the advantage of this method. For patients having normal function of the posterior tibial muscle, the Cobb procedure may be more suitable. Conclusion The soft tissue reconstruction procedures of AAFD should be chosen individually based on the stage and type of the deformity.