"Who will win the elections? There is one thing of which I am sure and certain, and that is that I will not lose them," Kabila told a press conference in Kinshasa.
Asked if he would step aside if he is defeated in the November 28 polls, Kabila, who has been head of state since the 2001 assassination of his father Laurent, said "the answer is yes".
"One can always do something else if one loses an election, there are other things besides politics. But we will not lose the election," he said.
Twelve candidates, including Kabila and veteran opposition leader Etienne Tshisekedi, have registered to run to be head of state in the upcoming ballot.
Kabila's comments came after his long-time rival Tshisekedi himself declared that he was certain to win the single-round presidency vote.
Since July, four successive rallies by Tshisekedi's party have degenerated into fights with the police and on Monday the UN Security Council called for "credible and peaceful" elections in the vast mineral-rich nation.
The Security Council members "recall the importance of free and constructive political debate", Nigeria's UN ambassador, Joy Ogwu, the current council president said, urging "equitable access to media and safety to all candidates".
Meanwhile, the US-based Carter Centre, which has had observers in the country since August, said there were "serious threats to holding the election" and called for the DRC's election commission to take "urgent steps" so as to be credibly prepared for the ballot.
The commission must "take rapid and convincing steps to ensure the transparency and credibility of the voter register", the centre said.
It added the commission needed to "ensure the timely distribution of all necessary election materials across the country, as well as other associated scheduling and logistical tasks; and to provide additional resources to implement civic and voter education in advance of election day".
"The DRC is a large and fractured country with a violent past and present; failure to recognise this context, or worse, to exploit it for electoral gain, will undermine the possibility of genuine democratic elections," the centre established by former US president Jimmy Carter said.
Tshisekedi served as prime minister during dictator Mobutu Sese Seko's regime and was leader of the Union for Democracy and Social Progress (UDPS).
Systemic corruption since independence from Belgium in 1960 and internal conflict since 1997 have slashed the nation's national output, increased external debt and led to the deaths of more than five million from violence, famine and disease.
Some 32 million Congolese are eligible to vote in the November 28 presidential and legislative elections.
Kabila said the already delayed legislative polls may take place on the same date, "if we can confirm that the independent national electoral commission is ready to organise the elections".