That's according to the Stockholm International Peace Research Institute in its "Yearbook 2007."
The report released June 11 says that the United States accounted for nearly half the spending last year, at $529 billion.
It dwarfed its nearest rivals, Britain, France, China, and Japan, which each accounted for about 4 to 5 percent of the total.
Russia lagged behind, spending an estimated $35 billion in 2006.
As in years past, the United States and Russia still led the world in selling arms in 2006, while China and India were the fastest growing arms purchasers.
Mark Bromley, a research associate for SIPRI's Arms Transfer Project, says Russia has been looking further afield for big customers in the past couple of years -- and with some success.
(For more on the report, read RFE/RL's interview with Bromley.)