The country's banks do not adhere to Western banks' environmentally-conscious "Equator Principles" of lending, and its companies are not required to be transparent about their deals with African dictators.
Beijing cynically sold arms to both sides in the war between Eritrea and Ethiopia. It has swooped on investment opportunities in countries shunned by the West, such as Zimbabwe and Sudan. Its close relationship with Khartoum appears to have played a role in the UN's failure to take serious action against Sudan in relation to massacres in Darfur.
Human Rights Watch has condemned Beijing's attitude.
"China can't continue to protect human rights abusers at the expense of civilians just because it is profitable to do so," says Peter Takirambudde, the group's Africa director.
It is also claimed that some local industries are being snuffed out by cheap Chinese imports. Overall, however, Africa's annual GDP growth is a healthy 6 percent, and some experts suggest the economic benefits that China brings outweigh even the political risks.
"Chinese companies are building roads and hospitals, and generally going where Western companies do not dare to go," says Feng Zhang, an analyst at the Foreign Policy Center think tank in London.
"I understand the concern over human rights but so far China's interest has been very good for Africa," he says.