This paper presents two optimization methods for solving the passenger train timetabling problem to minimize the total delay time in the single track railway networks.The goal of the train timetable problem is to determine departure and arrival times to or from each station in order to prevent collisions between trains and effective utilization of resources.The two proposed methods are based on integration of a simulation and an optimization method to simulate train traffic flow and generate near optimal train timetable under realistic constraints including stops for track maintenance and praying.The first proposed method integrates a cellular automata(CA) simulation model with genetic algorithm optimization method.In the second proposed approach,a CA simulation model combines with dynamically dimensioned search optimization method.The proposed models are applied to hypothetical case study to demonstrate the merit of them.The Islamic Republic of Iran Railways(IRIR)data and regulations have been used to optimize train timetable.The results show the first method is more efficient than the second method to obtain near optimal train timetabling. This paper presents two optimization methods for solving the passenger train timetabling problem to minimize the total delay time in the single track railway networks. The goal of the train timetable problem is to determine departure and arrival times to or from each station in order to prevent collisions between trains and effective utilization of resources for the two proposed methods are based on integration of a simulation and an optimization method to simulate train traffic flow and generate near optimal train time table under realistic constraints including stops for track maintenance and praying.The first proposed method integrates a cellular automata (CA) simulation model with genetic algorithm optimization method. the second proposed approach. a CA simulation model bent with dynamically dimensioned search optimization method. The proposed models are applied to hypothetical case study to demonstrate the merit of them. Islamic Republic of Iran Railways (IRIR) data and regulations have been used to optimize train timetable. The results show the first method is more efficient than the second method to obtain near optimal train timetabling.