South Africa has been ranked 69 of 176 countries in Transparency International's Corruption Perception Index 2012 (CPI), which was released on Wednesday.
The CPI ranks countries in order of those with the least perceived corruption in the public sector to those with the most.
South Africa tied with Brazil and Macedonia, on a score of 43. It was ranked 64 in 2011 and 54 place in 2010.
Botswana, ranked 30 with a score of 65, was perceived as the African country with the least corrupt public sector.
Other African countries which ranked above South Africa were Cape Verde (39), Mauritius (43), Rwanda (50), Seychelles (51), Namibia (58), and Ghana and Lesotho (both 64).
The countries perceived to have the least corrupt public sectors were Denmark, Finland and New Zealand, which all scored 90.
Ranked 174, Somalia, North Korea and Afghanistan were perceived as having the most corrupt public sectors, with a score of eight. The same as last year.
African countries made up 13 of the bottom 30 countries in the world.
Zimbabwe was ranked 163, Chad 165 and Sudan 173.
"Two thirds of the 176 countries ranked in the 2012 index score below 50, on a scale from 0 [highly corrupt] to 100 [highly clean], showing that public institutions need to be more transparent, and powerful officials more accountable," Transparency International said in a statement on its website.