This study presents a model-based analysis of the ground connectivity performance of the future Santa Lucia-Mexico City multi-airport system. The plan of the current government is to connect the two airports by a dedicated line, either by bus or other transport so that passengers and airlines can get the benefit of a coordinated operation. Performance indicators such as minimum connecting time, vehicle utilization and passenger waiting time are used to evaluate the future performance. Results reveal that when all passengers are allowed to use the connection, a big number of vehicles are required for providing a good level of service while in the case of a restricted use to only transfer passengers the operation with Bus would have a good performance.