The camp, located in Kamina in southeastern Katanga province, houses ex-militiamen and former rebel fighters now being retrained to serve in a unified army.
Defence Ministry spokesman Delion Kimbu said at least a thousand soldiers arrived at the training camp this week to find insufficient food rations there.
"Many soldiers had walked large distances to reach Kamina, they were fatigued and hungry," Kimbu said, adding that the dead soldiers had once belonged to traditional Mayi-Mayi militia units once active in the region during a 1998-2002 war that drew in the armies of half a dozen African nations.
United Nations officials say conditions are dire at many army training camps, where outbreaks of disease spread rapidly among soldiers crammed into decrepit buildings without electricity or running water.
"Our military observers confirmed that six soldiers died of hunger. It looks like the government has not been feeding these soldiers for quite some time," said Alexander Essone, a UN spokesman in the regional capital, Lubumbashi.
"The Congolese government has contacted the UN today to ask us to supply them with chicken and other food, we are considering their request," Essone said, adding that he expected some UN assistance to reach the Kamina camp in the next day or two.
"Many soldiers had walked large distances to reach Kamina, they were fatigued and hungry"
Defence Ministry spokesman
Congo is integrating belligerent groups from its war to form a new national army, but progress has been slow with fewer than half of the 18 army brigades planned for this year ready for service.
The freshly integrated brigades have also found it difficult to shake off old habits, still largely functioning along wartime rebel chains of command.
Though the government does provide food at some of its two-month long training programmes, the vast majority of trainees are expected to fend for themselves.
Most attend with their families to cook and care for them during training.
Soldiers have repeatedly protested about poor living conditions at the camps, and some half a dozen local mutinies have occurred in the past six months.