In this study, we address the secure model predictive control (MPC) problem for a system comprising unmanned aerial vehicles (UAVs) and unmanned ground vehicles (UGVs). Our objective is to cooperatively regulate the UAV -UGV system to maintain all states at equilibrium in spite of physical constraints, external disturbances, and Denial of Service (DoS) attacks on communication channels. We propose a dynamic event-triggered distributed MPC (DET-DMPC) approach. Initially, a robustness constraint is integrated into the MPC to incrementally confine system states within a progressively narrowing tube, thereby bolstering disturbance resilience. Additionally, we introduce a neighbor output sequence prediction mechanism (NOSPM) to mitigate packet loss due to DoS attacks. In response to the varying durations of DoS attacks, we have developed a DET mechanism equipped with adaptive triggering thresholds. Moreover, we have formulated sufficient conditions that ensure the recursive feasibility of the DMPC algorithm and the stability of the UAV-UGV system. Comparative tests demonstrate the proposed DET-DMPC's superiority in robustness and security.