A kangaroo "in a bad mood" has left a man in hospital on the South Coast, after attacking the 80-year-old on Thursday.

NSW paramedics treated the man about 10:45am in Bendalong for multiple cuts to his lower legs suffered during the attack, including "one and a half inch lacerations below the knee".

The offending roo looks on as paramedics treat the injured man. Credit:NSW Ambulance Service

Attending Paramedic Rob Hilliar said the man fed the local roos each morning and one had become particularly aggressive.

"He's a lovely bloke who spoils them a little, feeding them jam and cream on toast," Mr Hilliar said.