In doing so, they limited the Billikens to a program-tying 10 first half points on just 4-for-23 field goal shooting.
Meanwhile, the Sooners got everything they wanted at the other end of the court, hitting 15-of-24 field goal attempts in The Opening 20 minutes, including half of their eight tries from behind the arc.
That enabled OU to get up by as much as 33 in the first half en route to seizing a sizable 40-10 halftime advantage.
The Sooners put it in cruise control from there, though they didn't score until after the first media timeout.
From that point, though, OU built it up to as much as 35 when guard Morgan Hook canned a three inside the five-minute mark.
Forward Nicole Griffin paced a balanced Sooner scoring effort with her game-high 15 points on 7-for-10 shooting.
For the Billikens, there wasn't much scoring to be found, but guard Jacy Bradley did manage 11 on her 5-for-13 shooting.
The Sooners, a few days off struggling mightily on the boards against UCLA, out-rebounded Saint Louis 37-25.
Hand led the way in that category with her six.
OU hit 49.1 percent of its shots, while Saint Louis shot an abysmal 27.7 percent.
The Sooners get back to action when they head to the Rainbow Wahine Showdown and first face Arkansas at 7 p.m. Friday.