The annual report by the University of Central Florida's Institute for Diversity and Ethics in Sport showed overall academic progress, but 21 schools graduated fewer than 50 percent of their black football players, the study found. That's up from 19 last year.
Richard Lapchick, the institute's director, said the widening gap between whites and blacks was surprising because the numbers had closed in recent years.
"That could be a temporary blip, but it certainly caught me by surprise," he said. "I think part of it is the urban education system where a lot of the African-American students come from is so depleted. Too many student-athletes recruited from those areas are so far behind when they come to college, it's difficult to catch up."
The study was based on NCAA statistics collected from member institutions.
The analysis is of the 67 schools that had accepted bowl invitations by Monday.
"There is still room for improvement, but the trend lines are generally moving in the right direction," NCAA spokesman Erik Christianson said in a statement.
The study showed 57 schools had graduation success rates of 66 percent or higher for white football players, nearly triple the number of schools with equivalent graduation success rates for black football players. That's up from 56 schools last year.
Four schools had graduation success rates for black football players that exceeded rates for white players -- Connecticut (5 percentage points higher), Troy (7 points higher), Southern Miss (8 points higher) and Rutgers (4 points higher). That was down from five schools in last year's study.
Lapchick said getting more minorities in administrative positions -- such as head coaches and athletic directors -- could help curb the numbers.
He also said he will be looking closer at financial issues to see how much, if at all, the economic downturn is affecting the numbers.
Despite the growing racial disparity, overall progress grew.
About 90 percent of the teams surveyed this year received a score of more than 925 on the NCAA's Academic Progress Rate, up from 88 percent last season, according to the report. Sixty-one of the 67 schools had at least a 50 percent graduation rate for their football teams, the same as a year ago.
Dave Czesniuk, the director of operations for Northeastern University's Sport in Society, said analysts will have to monitor those figures next year to see whether it's the beginning of a trend.