The officials told The Washington Post there were 349 active-duty suicides last year, compared with 229 combat deaths in Afghanistan.
The figures might be slightly revised later this year after 2012 deaths have been fully investigated, they said.
The Army, the military's largest force, had 182 suicides in 2012, compared with 159 in 2011.
The Marine Corps saw its 2012 rate rise by 50 percent to 48 suicides.
The Navy recorded 60 suicides, representing a 15 percent increase, while the Air Force reported 59 suicides, an increase of 16 percent.
Traditionally, the Navy and Air Force have had a lower suicide rate than the Marines and Army.
"We are deeply concerned about suicide in the military, which is one of the most urgent problems facing the department," said Pentagon spokeswoman Cynthia O. Smith. "We are committed to taking care of our people, and that includes doing everything possible to prevent suicides in the military."