Though booking train tickets online from the official website of China Railway Company is very popular among Chinese travelers, it is nearly impossible for individual travelers to book a train ticket to Lhasa by this way. Because most train tickets are reserved by travel agencies.
The best and secure way for foreign tourists to book Tibet train tickets is by using a reputable online travel agency, which will charge a service fee. Some travel agencies have an annual reservation from the ticket office, so they can get tickets much easier that others.