During the driving process of Dual Clutch Transmission (DCT) vehicles, the driving intention reflects the short-term driving expectations of the driver. The DCT vehicle power transmission system is a complex nonlinear coupled system, which has problems such as large shaking, unstable performance during starting, and significant jerk during starting with increasing service time, as well as clutch erosion. The driving intention and internal excitation of the vehicle's power transmission system have a significant jerk on the dynamic characteristics and quality of the vehicle's starting. However, existing research has not fully considered the coupling effect of driving intention and internal excitation of DCT transmission system on the dynamic characteristics of DCT vehicle starting. In order to analyze the coupling effect of driving intention and internal excitation of DCT vehicle transmission system on the dynamic characteristics of DCT vehicle starting, a DCT vehicle coupling dynamic model considering internal and external excitation was established. Based on the established DCT coupled dynamic model, the influence of different driving intentions such as gentle start, normal start, and emergency start on the overall dynamic characteristics of DCT vehicles during the starting was analyzed. Through the above research work, the coupling effect of internal excitation factors and driving intentions in the DCT vehicle transmission system on the dynamic characteristics of the DCT vehicle during the starting has been obtained. This lays the foundation for improving the starting quality of DCT vehicles.