Northern Territory police said in a statement that local rangers killed the crocodile with the permission of the Traditional Owners, who are the region's indigenous landowners.
What is known about the fatal attack
A 12-year-old girl had been swimming with her family last week when she was attacked and killed by a crocodile in Mango Creek, near the remote Palumpa community in Australia's Northern Territory.
On Thursday authorities found the girl's remains two days after she was attacked.
Wildlife rangers had been trying to trap or shoot the crocodile since the fatal attack. Police said it was located on Sunday and shot.
Analysis confirmed that it was the animal responsible for the fatal attack, according to police.
"The events of last week have had a huge impact on the family and local police are continuing to provide support to everyone impacted," police spokeswoman Erica Gibson said. "The family have requested privacy as they grieve."
The girl's death came just weeks after regional authorities approved a 10-year plan aimed at containing crocodile numbers by lifting the rate of culling near human habitats from 300 to 1,200 a year.
The Northern Territory recorded the deaths of 15 people in crocodile attacks between 2005 and 2014 and another two in 2018.