To enhance the frequency support characteristics of grid-forming (GFM) wind turbines under matching control, and to overcome the poor adaptability of single control strategies and fixed parameters to varying power grid operating conditions, this paper proposes a fast frequency support strategy for GFM permanent magnet synchronous generator (PMSG) wind turbines based on linear active disturbance rejection control (LADRC). First, a GFM control architecture of grid-connected PMSG based on matching control is constructed, and the matching mechanism between DC voltage and frequency is explained. Second, an LADRC-based frequency support strategy for matching control GFM PMSGs is designed, and the influence of controller bandwidth parameters on the disturbance rejection capability of LADRC is analyzed. Then, a genetic algorithm (GA) is integrated to perform online optimization of the bandwidth parameters in LADRC, endowing the controller with a certain degree of self-tuning capability. Finally, comparative analyses of grid frequency and wind turbine power output under different operating conditions and control strategies are conducted using the PSCAD/EMTDC simulation platform. Simulation results show that the proposed strategy can enhance the frequency support capability of grid-connected wind power systems under various scenarios.