Mukherjee will join the heads of governments and states from more than 53 countries, including US President Barack Obama, in the two-hour long memorial service to be held at a 95,000-seat FNB Stadium, where Mandela made his last major public appearance during the 2010 football World Cup.
Mandela, 95, who had been suffering from a recurring lung infection and a prolonged spell of ill-health, died on December 5.
Scores of other foreign dignitaries have already arrived in the country
President Mukherjee is accompanied by UPA Chairperson Sonia Gandhi, Leader of Opposition Sushma Swaraj, Union Commerce Minister Anand Sharma, CPI-M leader Sitaram Yechury and BSP leader Satish Mishra, reflecting the high-esteem Mandela held across the entire political spectrum in India.
He is one of only six heads of state who will address the crowd at the memorial service. He will join Obama, Brazilian leader Dilma Rousseff, Hifikepunye Pohamba of Namibia and Raul Castro of Cuba as well as Chinese Vice-President Li Yuanchao on the podium to address the crowd.
Mukherjee summed up the mood when he said shortly before leaving for Johannesburg that his visit to South Africa "reflects the high degree of love and respect which Dr Mandela commanded in India." "My delegation and I hope to convey to the government and people of South Africa the intense grief and personal loss that we in India feel over the sad demise of the great soul - our beloved 'Madiba'," he said.
"His life was a living example of human strength and courage in the face of brute force and gross injustice. He was the last of the giants who led the world's struggles against the colonialism and his struggle held special significance for us as we saw in him a reflection of our own prolonged anti-colonial struggle led by Mahatma Gandhi," he said.
After today's memorial service, Mandela's remains will lie in state for three days at the government buildings in Pretoria, the same where he was sworn in as president in 1994. He will be buried on Sunday in Qunu, 450 miles south of Johannesburg, at an event only a few world leaders are expected to attend.
Scores of other foreign dignitaries have already arrived in the country for the memorial service. There has been an "unprecedented interest" to attend the revered statesman's funeral, South African Foreign Minister Maite Nkoana-Mashabane told a news conference here.