Seven of them were killed on Friday and Saturday, SANParks spokesman Reynold Thakhuli said in a statement.
Four hunting rifles, ammunition, poaching equipment and a pair of horns were seized.
The poachers were killed by park rangers and members of the SA National Defence Force, in an attempt to curb rhino poaching in the park, Thakhuli said.
Aggressive towards rangers
"They [poachers] operate in groups of four to six and are aggressive and engage and shoot at the rangers on sight, creating a daily life-threatening situation."
Thakhuli said two other poachers were arrested and eight firearms were seized in January.
"Up to 15 heavily armed groups operate in the KNP at any given time, especially during the full moon period," he said.
Forty rhino have been killed in the KNP in the past year.
"This has brought more resolve from the Rangers' Corps to double their efforts to keep the species alive," he said.
Prevention strategy
Ranger commander Maj-Gen Johan Jooste said he was optimistic about the park's long term poaching prevention strategy.
He said that poaching incidents in the park had decreased from 72.6% in 2012 to 42.6% in 2013, and that 123 people were arrested in connection with poaching activities in 2013.
"It is now up to the prosecuting teams, investigators and the [SA Police Service] to conclude what we have started," Jooste said.
Read more:
181 rhinos killed in SA in 2012
More than 1000 rhinos poached in 2013