With respect to population growth, particularly in developing countries like Iran, this trend has caused people to use personal vehicles more than ever so that application of personal vehicles is more than predicted traffic capacity and potential in towns and megalopolises. This has created several traffic and environmental problems and casualties and financial losses in urban community. For some period of time, the experts and specialists in the field of traffic and urban administration are thinking about some alternative solutions to resolve these problems. One of such alternatives to substitute with using personal vehicle is establishment, development and renovation of public transportation system in all dimensions of megalopolises. At the present essay, it has been tried to explore into public transportation system of Tehran City as one megalopolis and with respect to planning objectives of public transportation in Tehran City, we will deal with the problems and difficulties which this plan is faced by them and eventually by purposing some solutions including optimization of system capacity and accessibility to network, reducing trip time and presentation of some strategies to improve mental imagination of public in using public transportation, we have contributed to create an integrated, efficient and reliable public transportation system.