The scientific evaluation of the lane side traffic capacity at the airport departure level can enhance the operational efficiency of the airport and the travel experience of passengers. Taking the Jinan Yaoqiang International Airport as an example, the research on the evaluation and optimization of its traffic capacity is conducted by combining analytical method with VISSIM simulation. Firstly, the traffic flow parameters of the lane side at the airport are obtained through on-site measurements, and the current traffic capacity value is calculated based on the lane side traffic capacity model. Secondly, a simulation model is built using VISSIM software to simulate the traffic capacity of the lane side according to the traffic volume of the airport and the measured geometric data of the roads. The results demonstrate that the error of the results obtained from the analysis method and VISSIM simulation is within 10%, verifying the reliability of this method. Finally, aiming at the current situation of the airport, the optimization measures are proposed from the aspects such as time-limited parking at the lane side and the functional zoning of lanes, and the simulation verification is conducted. The results reveal that the optimization effect is relatively significant, and the lane side traffic capacity has increased by approximately 32.34% after optimization. The research result can offer a theoretical basis and technical support for the design and management of airport lane side.