To achieve high-accuracy tracking of dual-linear-motor-driven (DLMD) gantry, high-level synchronization between redundant actuators is a nonnegligible factor and also a difficult issue to be solved prior. Especially, when both XY axes are simultaneously operating to accomplish complex tasks efficiently, additional coupling effects will be generated by the dynamic load presented on the crossbeam, which makes the synchronization issue more complicated compared to the case with static load. However, due to the absence of an accurate model to fully reveal the complete coupling characteristics, existing approaches to this issue still have inherent limitations. Therefore, this paper focuses on the systematic physical modeling and synchronization control of DLMD gantry with a dynamic load presented on the crossbeam. A complete coupling mathematical model is established firstly, by fully considering two linear motions (X-axis and Y-axis) and also including the additional rotational motion of the crossbeam. Built upon the effective model information, corresponding solutions by compensating the dynamic load effects and actively controlling the rotational dynamic to regulate the internal forces have been proposed, leading to a novel adaptive robust synchronization control method. Comparative experiments are carried out, and the results show the effectiveness and superiority of the proposed method in dealing with synchronization issue subjected to dynamic load effects.