The invention discloses a vehicle quality estimation method considering gear shifting and road slope factors. The vehicle quality estimation method comprises the following steps that 1, data are collected, specifically, (11), the vehicle driving state data are collected through a data collecting device, and (12), parameters required by a model are calculated and obtained by combining vehicle intrinsic parameters with the vehicle driving state data; 2, based on the obtained vehicle driving state data, a vehicle longitudinal dynamic model is established; 3, a vehicle quality estimation model considering the gear shifting factor is established; 4, a transmission system mechanical efficiency estimation model is established, and the transmission system mechanical efficiency estimation model and the vehicle quality estimation model which considers the gear shifting factor and is provided in the third step jointly form a vehicle quality estimation model which considers the gear shifting and road slope factors simultaneously; 5, the use condition of a vehicle quality real-time estimation system is determined; and 6, the collected vehicle driving state data and relevant model parameters are input into the vehicle quality real-time estimation system to estimate the real-time vehicle quality.