The invention relates to a steel tank type composite material balance block. The steel tank type composite material balance block is composed of a steel tank and composite materials, and the steel tank is filled with the composite materials. The steel tank type composite material balance block is characterized in that the steel tank is of a cuboid tank shape, a middle tank is arranged in the steel tank, side tanks and concave tanks are arranged on two sides of the middle tank respectively in a mirror symmetry mode, casted ribbed plates are used for separating the tanks, and a connecting through hole is formed in the lower portion of each ribbed plate. According to the character of the balance block, the divided tanks in the steel tank are of a balanced type structure, the middle portion is heavy, and two side portions are light. Accordingly, the operating efficiency of the balanced block and the balanced capacity are improved, the bob-weight of the balanced block is novel, and the bob-weight technological level of elevators and cranes is improved.