A "Hybrid"vehicle is one that has the potential to operate in more than one environment. This work demonstrates a robust backstepping control algorithm for the autonomous transmedia operation of a hybrid unmanned aerial-underwater vehicle in the presence of uncertainty. The simplified mathematical model is considered to depict the entire controller design procedure. The numerical simulation is carried out to demonstrate the proposed control system's efficiency and compare it to existing PID control. The vehicle's transient behaviour is compared in six different transmedia manoeuvres between air and water. The suggested control system is evaluated for stability in aerial manoeuvres and transmedia manoeuvres with respect to the conventional PID algorithm in the MATLAB-Simulink environment to demonstrate the superiority of the proposed algorithm. © 2023 ACM.