There is no direct train from Tsinghua University to Beijing Railway Station. Because of the distance, most people are willing to transfer to the subway. You can take Bus No.375 and Bus No.743 to Xizhimen or Chegongzhuang at Tsinghua University Ximen or Tsinghua Campus (Tsinghua Nanmen Bus Station), and then transfer to Metro Line 2 to Beijing Station. When I have time, I want to see the downtown area of Beijing. Take bus No.4, No.726 and No.826 at Tsinghua University Ximen or Tsinghua Park Station to the front door, and then take the subway to Beijing Station.