Holyfield, who last held a version of the heavyweight title in 2000, was wobbled by Ibragimov in the seventh round and again in the 10th.
The veteran's record is now 42-9-2, while Ibragimov improves to 22-0-1.
Holyfield was aiming to upset the odds and also become the second-oldest ever heavyweight world champion after fellow American George Foreman.