Pure electric buses are widely used in urban public transportation, but different cities have different station spacing, road conditions, operating hours, and traffic situations. This leads to biases in evaluating vehicle power parameters and energy consumption. Therefore, it is challenging to achieve an optimal balance between power performance and economic efficiency. This paper proposes a power parameter optimization method for pure electric buses based on urban driving cycle. Firstly, we construct a time-sensitive and geographically specific urban driving cycle based on the actual bus traveling data. Secondly, we build an equivalent vehicle model to simulate the performance and power consumption under different driving cycles, and improve the range through parameter matching. Finally, the sparrow search algorithm is used to optimize the design parameters of the main gearbox and motor, aiming to enhance the matching and energy-saving performance of the entire vehicle power system. The results show that this method can effectively improve vehicle dynamics and e economic efficiency, providing valuable theoretical support for energy conservation and environmental protection technologies in urban transportation.