Abstract: The large aperture and high observation frequency requirements of radio telescopes impose stringent demands on servo system control performance. To address common nonlinear coupling issues in antenna systems, such as dead zones, saturation, and backlash, this paper proposes an H-W (Hammerstein-Wiener) model-based nonlinear modeling method for antenna servo systems. A four-step identification process is designed to estimate the input nonlinear module, dynamic linear module, and output nonlinear module of the H-W model. Validation using identification data from the 26 m radio telescope in Nanshan, Xinjiang, demonstrates that the H-W model outperforms traditional linear system models in describing the overall dynamic characteristics of the antenna.