The Serbian sixth seed fought back after losing the opening set against the top-seeded German before producing another determined performance to maintain his perfect record in Beijing.
The victory moved Djokovic to 32-0 at the China Open, surpassing Rafael Nadal's previous Open Era record of 31 consecutive victories from the start of a tournament at Roland-Garros.
Djokovic had equalled Nadal's mark on Friday when he recovered from a set down to defeat China's Bu Yunchaokete 4-6, 7-6(2), 6-2 in the second round. That victory took his Beijing record to 31-0.
Against Zverev, however, Djokovic faced a significantly tougher challenge. The German claimed the opening set 6-4, putting the six-time Beijing champion under immediate pressure.
Djokovic responded in the second set, raising his level and forcing the contest into a decider. He then maintained his composure in the third set to complete another comeback victory and extend his remarkable record at the ATP 500 tournament.
The result also sends the 24-time Grand Slam champion into another China Open semi-final, continuing a remarkable run at an event where he has previously won six titles. Djokovic had not competed in Beijing since 2015 before returning for this year's tournament.
At 39, Djokovic is also continuing to defy age at the ATP 500 event. His victory over Bu had already made him the oldest ATP 500 quarter-finalist since the category was introduced in 2009, surpassing Roger Federer's previous mark.
The Serbian's Beijing campaign has been particularly notable given the physical difficulties he has experienced during the 2026 season. Djokovic revealed after his victory over Bu that he had been dealing with health issues and described the season as a major struggle, although he felt an improvement in his condition during the latter stages of that match.
His return to Beijing has nevertheless produced a remarkable sequence of results.
Djokovic's Beijing record:
• 32 wins, 0 defeats at the China Open
• Six-time champion in Beijing
• New Open Era record for consecutive victories from the start of a tournament
• Previous record: Rafael Nadal, 31-0 at Roland-Garros
• 24 Grand Slam titles
Djokovic will now turn his attention to the semi-finals as he continues his bid for a seventh China Open title and another piece of history in Beijing.