There are an estimated 49.32 million people in South Africa, Statistics SA said on Monday.
Black people were in the majority (39.14 million) and constituted a little more than 79 percent of the total population, the Pretoria-based agency said.
The white population was estimated at 4.47 million, the coloured population at 4.43 million and the Indian/Asian population at 1.28 million.
Fifty-two percent (25.45 million) of the population was female.
Gauteng comprised the largest share of the country's population with about 10.53 million people (21,4 percent) living in the province.
KwaZulu-Natal had the second-largest population, with 10.45 million people (21,2 percent) living there.
With a population of approximately 1.15 million people (2,3 percent), the Northern Cape had the smallest share of South Africa's population.
The rate of growth for the country's population declined between 2001 and 2009.
"The estimated overall growth rate declined from approximately 1,38 percent between 2001-2002 to 1,07 percent for 2007-2009. The growth rate for females is lower than that of males."
At mid-year 2009 around one-third of the population was aged 0-14 years and around 7.5 percent was older than 60.
The total number of people living with HIV increased from an estimated 4.1 million in 2001 to 5.2 million by 2009.
"For 2009, an estimated 10,6 percent of the total population is HIV positive."
Around one-fifth of South African women in their reproductive ages were HIV positive.
The total number of people living with HIV was estimated at 5.21 million.
For adults aged 15-49 years, an estimated 17 percent of the population was HIV-positive.
For 2009 Statistics SA estimated that approximately 1.5 million people aged 15 and older, and approximately 106 000 children would need antiretroviral treatment.
The total number of new HIV infections for 2009 was put at 413 000.
Of these, an estimated 59 000 would be among children.
Life expectancy at birth was estimated at 53,5 years for males and 57,2 years for females.
The infant mortality rate was estimated at 45,7 per 1 000 live births. - Sapa