Starting July 1, delivery of perishable items can only be made by courier, which some sellers say will make shipping unaffordable for many regional customers.
The prohibited items include meat, seafood, milk and eggs.
Supporters of small businesses fear that the move will be bad for farmers and producers.
In a statement, the Australia Post said:
"Due to the complex food safety and regulatory requirements that differ between states and territories, Australia Post will stop shipments of certain foods from 30 June 2021."
"We understand the impact this decision has on many manufacturers and we are currently working with our customers and industry regulators to define the way forward."
