The 24/7 dog off-leash area at Lady Robinsons Beach, Kyeemagh has been extended until December 1.
Bayside Council made the announcement this week but added a warning.
"Please stay within the off-leash area," a council spokesperson said.
"There has been an increase of dogs found outside of the off-leash restricted area between gates 60 and 61 at Lady Robinsons Beach, Kyeemagh.
"Dog walking is not permitted on any other part of the beach and foreshore, be that on-leash or off-leash.
"Council Rangers have been providing warnings for dog owners but will now start to issuing fines."
Last August, Bayside Council decided to extend the hours of operation for the Off-Leash Dog Exercise Area at Lady Robinsons Beach, Kyeemagh to 24 hours a day until October.
Normally, the dog off-leash area operates before 10am and after 4pm.
The council decided to extend the hours because of the increase in people walking with their dogs during lockdown.
Bayside Council's permanent Off-Leash Dog Exercise Area at Lady Robinsons Beach, Kyeemagh opened in July, 2018 and has proven popular.
It's the only off-leash beach area for dogs between Kyeemagh and Sandringham.