Visitors to Australia have been warned not to feed kangaroos after marsupials started attacking people at a tourist hotspot near Sydney.

Thousands of people visit Morisset Hospital in southern Lake Macquarie every week in order to get close to kangaroos that gather on the grassy slopes.

Signs warning tourists not to feed the creatures have been pinned to trees in the area, which is less than a two-hour train ride from the city in New South Wales.

"There are people getting kicked and scratched at least every day," Shane Lewis, tourist shuttle bus driver, told ABC News.

"One lady got 17 stitches in her face from her eye to her chin."