The highest incidence of poaching took place in the Kruger National Park (KNP) with 146 rhinos killed, spokesperson Reynold Thakhuli told Sapa.
The North West province followed with 57 rhino deaths, and Limpopo closely behind with 52.
KwaZulu-Natal was at the bottom of the list with only 38 reported rhino killings last year.
Thakuli said 162 people linked to poaching the animals had been arrested.
"You see, the investigation takes a bit of time and many cases are still pending. We expect prosecutions soon."
He said authorities were intensifying their efforts to clamp down on poachers in South Africa.
Last year five poachers caught in the act were shot by the authorities while in the first month of 2011 the figure stood at six - five in the KNP and one in the North West province. January 2011 has so far seen five rhino killings in the country - two in the KNP, two in Limpopo, and one in the Eastern Cape.