CBOT July corn settled up 1/2 cent at $3.54-1/4 per bushel while new-crop December ended up 1/4 cent at $3.75-3/4.
Rally capped by favorable Midwest weather that has bolstered US crop production prospects.
The US Energy Information Administration said weekly US output of corn-based ethanol rose to 1.06 million barrels per day, while stocks of the biofuel fell to 21.65 million barrels.
Ahead of the US Department of Agriculture's weekly export sales report on Thursday, traders expected the government to report US corn sales at 850,000 to 1,400,000 tonnes (old and new crop years combined).
South Korea's Major Feedmill Group purchased about 138,000 tonnes of corn in an international tender on Tuesday, bringing a surge in Korean corn purchasing this month to just over 1.5 million tonnes, European traders said.