Eaton, an alumnus of the University of Oregon, Saturday surpassed the 2001 all-time record of 9,026 set the Czech Republic's Roman Sebrle as well as the American record of 8,891 held by Dan O'Brien.
The 24-year-old shook off persistent rains during the competition, keying the victory in the 10-event trial with a javelin toss of 193 feet, 1 inch in the ninth event.
He then went on to become the 13th American to hold the world decathlon record with a lifetime-best time of 4 minutes, 14:48 seconds in the concluding 1,500-meter run.
"I truly love the event for what it represents for me," Eaton told the San Francisco Chronicle. "To me, it's my whole world. To do the event the best I possibly could makes me feel very good."
He and two-time world champion Trey Hardee, the weekend's runner-up, now advance to the Summer Olympics in London.