Abstract: According to the operation requirements and train characteristics of city railway, from the aspects of depot-yard turnout type, train maintenance system, signaling system model and depot-yard signal machine point layout scheme, the impact of the above factors on train exit efficiency from depot-yard is analyzed. Taking the Li’ao Depot of Wenzhou Rail Transit Line S3 as an example, considering the signal machine distribution formats of one-time exit scheme and segmentation exit scheme, the four actual working conditions of depot process layout and different signal machine distribution plans under different conditions of maintenance system are simulated, and train exit duration is calculated.