The Buckeyes (29-3) were led by center Jessica Davenport with 21 points.
The Eagles (21-11) were paced by guard Kindyll Dorsey with 24 points, including six three-pointers.
Boston College led by as many as 11 (20-9) in the first half.
The Buckeyes battled back and took their only lead of the first half (35-33) on a jumper from Debbie Merrill at the 2:03 mark.
But Dorsey closed the half with five straight points and the Eagles took a 38-35 lead with them into halftime.
A Kim Wilburn jumper gave OSU a 48-46 lead with 10:44 remaining in the game.
But Dorsey was on fire and continued to hurt the Buckeyes from the perimeter. Her final three-pointer of the evening gave Boston College a commanding 61-53 lead with 6:20 remaining.
Ohio State won at Boston College (66-61, OT) on Dec. 3, but was outplayed from start to finish in the rematch. The Buckeyes had the longest winning streak in the country entering play at 20.
Brandie Hoskins scored 13 points for OSU. But she had a tough shooting night (6 of 15), committed five turnovers, and also suffered a foot injury in the closing minutes.
Ohio State returns Davenport – the two-time Big Ten Player of the Year – next season, along with Hoskins and Packer. But the Buckeyes graduate key players such as Merrill, point guard Ashley Allen, and Wilburn. Merrill's toughness was a big reason this year's team was so successful up until the tournament.