The coupling effect between geometric configuration adjustment and flight trajectory generation in morphing aircraft is found to lead to issues such as a sharp increase in trajectory design variables. A gliding morphing aircraft was taken as the research object to analyze the configuration-trajectory coupling characteristics. A configuration-trajectory matching design model was established. A multi-fidelity aerodynamic approximation modeling method for morphing aircraft was proposed, and the dynamic equations considering the configuration-trajectory coupling effect were constructed. Based on a surrogate model and sequential quadratic programming, a configuration-trajectory integrated planning method was developed to conduct the matching design study, resulting in the optimal morphing design scheme under the best trajectory. The maximum range achieved by the variable-sweep-wing-span scheme is 2.16 times that of the fixed-configuration scheme and 1.26 times that of the variable-sweep scheme, thus verifying the effectiveness of the optimal configuration-trajectory matching design method. Methodological support is provided for the overall design of future intelligent morphing aircraft.