As the penetration rate of renewable energy resources in a new power system continues to rise while the proportion of traditional thermal power units continues to decline, the new power system faces severe frequency control problems. Distributed battery energy storage systems (BESSs) provide an effective way to solve these problems. On this basis, a robust load frequency control (LFC) method for distributed BESSs based on sparse communication network is proposed. To suppress the uncertainties related to system operation, a two-tier model predictive control (MPC) is designed to improve the response characteristics of BESSs, thus improving the performance of LFC. To minimize the area control error, the proposed method can satisfy various operating physical constraints of the system. In addition, the influence of communication delay on the performance of frequency modulation participated by BESSs is also considered, and a fuzzy coordination control device is designed to coordinate BESSs and the traditional generator, so that the mis-operation of the traditional generator under the condition of long delay can be avoided. Finally, simulation results show that the response capability and frequency modulation effect of distributed BESSs are better than the traditional methods under parameters such as different values of capacity, rated power, charge and discharge coefficient, state-of-charge and time constant.