The pumped storage power station has the characteristics of frequency-phase modulation, energy saving, and economy, and has great development prospects and application value. In order to cope with the large-scale integration and intermittency of renewable energy and improve the ability of pumped storage units to participate in power grid frequency modulation, this paper proposed a load frequency control (LFC) strategy for pumped storage units based on linear active disturbance rejection technology. Firstly, based on the operating characteristics of the pumped storage power station, the LFC model of the two-area reheat steam turbine under nonlinear conditions such as governor dead zone and generation rate constrains was established. Secondly, a second-order linear active disturbance rejection control (LADRC) was designed. The feasibility and control performance of the proposed LFC system were quantitatively analyzed through simulation. The results show that the LADRC has better control effect and stronger robustness than fractional-order proportion integration differentiation (FOPID) and traditional proportion integration differentiation (PID) controller. Finally, the pumped storage power station was added, and it was found that it has better correction performance under both generating and pumping operations, which greatly improved the dynamic response of secondary frequency modulation.