The injured kangaroo was found on Thursday in parklands near Melbourne's outer suburb, where it is believed to have survived for up to a week.
Melbourne Zoo vet Michael Lynch says he will monitor the kangaroo for the next three weeks but remains optimistic.
Wildlife Victoria has posted a Aus$10,000 ( US$7,600 ) reward to find the person responsible.
Wildlife Victoria spokeswoman Fiona Corke, said the kangaroo was rescued just days after another kangaroo was found with an arrow in its rump in the same area.
"It's just unbelievable, I can't believe that anyone would do something so cruel," she said.
The incident comes at a time when the Australian army is culling 6,000 kangaroos near the capital, Canberra - a move which has outraged conservationists.
The killings are intended to protect endangered plants and insects that share the grassy habitat with the kangaroos.
The kangaroo has been called Hope...
Und es war Ulli, die den Artikel gefunden hat, ich hab ja keine Zeit zum Suchen...)) Danke!