Other important US crops, including rice and soybeans, were also forecast to gain significantly, likely helping to keep a lid on the rise in global food prices in the first quarter of the year.
The USDA said US wheat production was solid, and coupled with strong increases in Russia, Ukraine and China, would take the total world crop for the 2014-2015 crop year to 716.1 million tons, up 2.0 million tons from 2013-2014.
US corn (maize) farmers meanwhile are expected to boost production by nearly one percent to 14.0 billion bushels (one bushel equals 25.4 kilograms of shelled corn), their largest crop ever.
The US rice crop is expected to be nearly 21 percent larger this year, and the soybean crop 16 percent, all helped by good weather over main Midwest and central plains growing areas.
The USDA cut its forecasts for wheat, corn and soybean prices but said the price for US rice would rise slightly from recent months.
The World Bank expressed concern in May over the rise in global food prices in the first quarter, the first such gain since prices surged to an all-time high in August 2012.