Emmerson Mnangagwa, the Zanu-PF secretary for legal affairs, said moments before the motion was accepted on Thursday: "This congress is requested to declare Comrade Mugabe as candidate for the 2008 presidential election."
Appetite for power
Earlier, senior party officials praised Mugabe who has ruled Zimbabwe since independence from Britain in 1980.
They described him as a distinguished revolutionary who defended the rights of Zimbabweans and Africans.
They did not mention the widespread accusations at home and abroad that Mugabe's government has stifled political opposition, abused human rights and turned Zimbabwe's once prosperous economy into one of Africa's poorest.
Mugabe had indicated in 2004 that he would step down when his current term of office expires.
But he has since appeared to regain his full appetite for power despite the economic woes in his country where inflation is now the highest in the world at nearly 8,000 per cent per annum.
In a speech before the uncontested endorsement of his candidature, Mugabe told his international critics to keep out of internal Zimbabwean affairs.