A foot balancing device includes a shoe insert, a main balancing element, three auxiliary force-transferring elements, and three auxiliary balancing elements. The main balancing element is provided in an arch region of the shoe insert and serves as a fulcrum on the shoe insert for the front part of the sole of one of the user's feet and the heel of the foot. The auxiliary force-transferring elements are provided in the arch region of the shoe insert so that the pressure center of the sole will displace along an ideal line. The auxiliary balancing elements are located forward of and on two lateral sides of the main balancing element respectively to support a transverse arch, inner arch, and outer arch of the foot respectively. Thus, the user's body weight can distribute evenly over the sole while the user is standing or walking, thereby preventing injury resulting from improper posture.