The Obama administration said the sharp increase follows steps it took over the past year to encourage alleged victims to come forward to report such abuse.
White House spokesman Jay Carney, who discussed the data at a briefing, said the new reporting suggests more “trust in the system.”
Carney also said the military has taken more disciplinary action in sex assault cases.
Details of the report are due to be released later in the day.
The issue received heightened attention from the Obama administration and Congress after last year’s report also showed a startling jump in reported sex abuse claims.