This win made the Americans the tenth consecutive World Cup unbeaten before the last four, as they were targeting their eleventh and fourth consecutive titles.
The United States led 50-33 in the first half and maintained their firm grip to face their last four matches against world number four Canada or 17th seed Puerto Rico, who are playing later.
Aja Wilson added 15 points and eight rebounds for the US while Yvonne Anderson scored 14 to lead Serbia in the Sydney Superdome.
It wasn’t easy at all for the Serbs, as the prolific United States went 28 games in a row undefeated, their longest since winning 26 games in 1994-2006.
They averaged 107.2 points in each of their five preliminary matches despite the absence of Wilson, Bloom and Chelsea Gray in their first two games, with the trio arriving late after the Las Vegas Ice won the WNBA Championship.
The two teams did not separate much in the first quarter, with the United States narrowly leading 25-23, recording 57 percent versus Serbia’s 48 percent.
The US has been tough on punishing fouls, stepping up the gear to dominate the board, and building 50-33 bullets. Connecticut Sun forward Alyssa Thomas led the scoring in a 12-0 career.
Serbia, seeded 10, was shooting just 30 percent from the field and holding only seven points in the third quarter, going more than eight minutes without scoring, before the Americans netted another 22 points in the fourth to land at home.
The only negative for the US was Kahleah Copper being helped with what appeared to be a thigh injury in the second quarter, after a severe crash.
In the other quarter-finals, China will meet France and hosts Australia, which qualified for the 2018 final, will meet Belgium later on Thursday.