Z-series (直达列车) is the most luxurious train service offered by China National Railway. Generally, Z-series trains are overnight, all-sleeper trains that have travel time of around 10–14 hours, with an average speed of around . Most Z-series trains have only soft sleepers. All but one of the Z-series trains stop at either Beijing or Beijing West.

Z stands for Zhida ("non-stop"). Most Z-series trains do not have any intermediary stops, not even technical stops for changing locomotives or drivers. However, two of these trains later had a few stops added to their schedule to boost the number of passengers.

List of Z-series trains (as of August 1, 2006):

• Z1: Beijing - Shanghai
• Z2: Shanghai - Beijing
• Z3: Beijing West - Hankou
• Z4: Hankou - Beijing West
• Z5: Beijing - Shanghai
• Z6: Shanghai - Beijing
• Z7: Beijing - Shanghai
• Z8: Shanghai - Beijing
• Z9: Beijing - Hangzhou
• Z10: Hangzhou - Beijing
• Z11: Beijing West - Wuchang
• Z12: Wuchang - Beijing West
• Z13: Beijing - Shanghai
• Z14: Shanghai - Beijing
• Z15: Beijing - Haerbin
• Z16: Haerbin - Beijing
• Z17: Beijing West - Changsha
• Z18: Changsha - Beijing West
• Z19: Beijing West - Xi'an
• Z20: Xi'an - Beijing West
• Z21: Beijing - Shanghai
• Z22: Shanghai - Beijing
• Z25/8: Wuchang - Shanghai South
• Z27/6: Shanghai South - Wuchang
• Z29: Beijing - Yangzhou
• Z30: Yangzhou - Beijing
• Z37: Beijing - Wuchang
• Z38: Wuchang - Beijing
• Z41: Tianjin - Shanghai
• Z42: Shanghai - Tianjin
• Z49: Beijing - Nanjing
• Z50: Nanjing - Beijing
• Z51: Beijing - Nantong
• Z61: Beijing - Changchun
• Z62: Changchun - Beijing
• Z73: Beijing - Hefei
• Z74: Hefei - Beijing
• Z77: Beijing - Hankou
• Z78: Hankou - Beijing
• Z85: Beijing - Suzhou
• Z86: Suzhou - Beijing