Abstract: Station arrival-departure capacity is one of the important parts in computer aided making train diagram. In this paper, around trains crossing and overtaking plan, the main reasons that cause the shortage of station arrival-departure capacity on single-track railway are systematically analyzed; a linear 0- 1 optimal model is built for the feasibility of station arrival-departure capacity requirement; and an effective algorithmwith time complexity beingO(n)is given for practical uses. The model coincides well with the general optimization of the train diagram. What’s more, it is helpful in flexibly designing a train algorithm; this is very important to the optimization of a train diagram and can also be used for double and multi-line railways.