<p>The linear active disturbance rejection control (LADRC) strategy, with its strong disturbance rejection and low reliance on an accurate system model, has been widely adopted in DC-DC converters. However, the control bandwidth parameter in the traditional LADRC is fixed, resulting in limited disturbance rejection capability of the converter under dynamic operating conditions. This paper proposes an adaptive linear active disturbance rejection control (A-LADRC) strategy for the asymmetric half-bridge (AHB) flyback converter. This strategy takes the output voltage error information of the converter as the basis of the control, establishes four distinct tracking phases in accordance with adaptive rules. Thus, it realizes the dynamic adjustment of the bandwidth parameters of both the observer and the controller. Meanwhile, it significantly improves the disturbance estimation capability of the observer, and effectively enhances the dynamic response and disturbance rejection performance of the output voltage of the converter. Theoretically, the stability and robustness of the closed-loop system are verified using the Routh-Hurwitz criterion and pole-zero map. Finally, experimental validation demonstrates that, under sudden load changes, the proposed strategy achieves an 84.3% improvement in response speed and a 69.8% reduction in overshoot compared with the LADRC.</p>