China is currently involved in a number of operations mining platinum, nickel and chrome ore in South Africa. Chinese companies are also heavily invested in light manufacturing, shipping, automobiles, telecommunications, construction and consumer electronics.
South African companies also view China as a lucrative market for their goods as well as a source of cheap labour.
Hu arrived in South Africa from Namibia, where he announced new development aid for the sparsely populated, mineral-rich desert country which hopes to benefit from an influx of Chinese investment and tourists.
In Namibia, the Chinese president announced a package of measures, including an interest-free loan and grants to build schools as he paid tribute to the "brotherly friendship" shown by a "young country full of vitality and talent".
Hifikepunye Pohamba, the Namibian president, who took office in March 2005, has actively promoted co-operation with China.
Namibia, which has a population of two million, is rich in diamonds and minerals such as uranium, zinc and cobalt.
It is also becoming an increasingly popular destination for Chinese tourists.
But Hu's tour comes amid growing criticism over rising Chinese domination in Africa, its interest-free, "no strings attached" loans and its support of governments with poor human rights records, such as Sudan and Zimbabwe.
South Africa is Beijing's biggest trade partner on the continent. But last year, Pretoria said that Africa needed to guard against developing a "colonial relationship" with China.
The opposition Democratic Alliance on Tuesday urged Mbeki to "ensure that if China is to play a large economic role in Africa, it must not be at the expense of good governance and sound human rights practices".
South African trade unions, meanwhile, have complained that Chinese textile imports are devastating domestic industry, forcing the two governments to sign a memorandum of understanding last year aimed at restricting imports.
South African investments in China amount to $400m including the ones by Anglo American and SAB Miller.
Of Hu's tour of eight countries, half are in southern Africa and the trip is expected to counter some criticism by boosting already growing trade ties and to ensure that aid pledges made by the Chinese premier last year at the China-Africa summit are carried out, such as reducing debt, increasing aid and cutting import tariffs.