Thousands of Zambians attended the funeral and were seated in tents erected at the parliamentary complex in the capital Lusaka. National flags flew at half-mast.
Mwanawasa, 59, died in a French military hospital last month after suffering a stroke in June. He had led Zambia since 2001 and was re-elected in 2006.
South African President Thabo Mbeki, Botswana’s leader Seretse Khama Ian Khama and the presidents of Namibia, Mozambique and Malawi also attended the funeral.
Mwanawasa’s copper-plated coffin was placed about five metres (yards) from the dais where leaders and officials were sitting.
Mwanawasa set himself apart from other regional leaders by speaking out about the political and economic crisis in neighbouring Zimbabwe, and was one of the fiercest critics of Zimbabwean President Robert Mugabe — who attended the funeral.
His tough stance against corruption in Zambia endeared him to donor countries and he was credited with turning the southern nation into one of Africa’s economic success stories.
Mwanawasa’s economic policies helped produce strong growth averaging 5 percent annually over the last six years, though many Zambians still live in poverty.
Vice President Rupiah Banda is acting president, and a presidential election is expected in November.
The ruling Movement for Multiparty Democracy (MMD) will choose its presidential candidate on Friday.
Mwanawasa’s widow Maureen told mourners at the funeral that she felt sorry most of all for the orphans Mwanawasa took care of through his local Baptist church.
"He was the father of all. It is the orphans he took care of that bring pain to my throat, they are orphaned again".