Federal regulators plan to accuse Sallie Mae, the giant student lending corporation, of charging military personnel excessive interest on student loans, and the government is looking into similar allegations against other lenders.

Sallie Mae revealed the pending action against it this week in its quarterly earnings report, stating that the Federal Deposit Insurance Corporation warned in July that it planned to take “new formal enforcement action” against the lender. Both corporations declined to describe the allegations, but Sallie Mae said they would deal in part with the Servicemembers Civil Relief Act.

That law caps interest on loans to military personnel at 6 percent, along with providing protections against default judgments and garnishments, and a person briefed on the matter said compliance with the 6 percent limit would be a key part of the F.D.I.C. action. Under the law, if a person borrows money at a higher rate and then enters the military and requests a lower rate, the lender must reduce the rate to 6 percent, and forgive any interest above that level.

“We’ve invested a lot in our compliance efforts, but we understand some concerns persist, and we realize that the bar is getting higher,” said Martha Holler, a Sallie Mae spokeswoman, adding that the corporation is “open to our regulator’s recommendations for improvement.” In recent months, Sallie Mae has created a Web site specifically for military personnel, and has taken other steps to notify them of their legal rights regarding student loans.