Julian Newman changed a number of timepieces including the 18th Century East Courtyard Clock Tower, which is twice as old as Big Ben.
Regulator wall clocks created by 18th Century clockmakers John Shelton and John Holmes were also changed.
Mr Newman, who has been keeping time at the palace for 12 years, described the process as "long" but "rewarding".
Blenheim Palace once operated on its very own "Blenheim Time", introduced by the 4th Duke of Marlborough and used until the 19th Century when Greenwich Mean Time (GMT) became universally adopted.
It was set by the complicated use of a sundial combined with the specific longitude of the Palace in relation to Greenwich.
Commenting on his challenge, Mr Newman said: "When the clocks go back it is a case of stopping each clock then going back exactly 60 minutes later and restarting them up again.
"I find it best to do this very early in the morning before the staff arrive as you can easily get tied up with other events and the last thing you want to do is lose track of the time."
A timekeeper at Blenheim Palace has had to change up to 30 antique clocks as British Summer Time ends.