The woman, who hasn't been identified, was preparing to shoot herself in the chest with a rifle when her German Shepherd leapt up and knocked into her, preventing the bullet from reaching her heart.
The Christian Post reported that the woman fired multiple shots from her 22-caliber rifle before turning the gun on herself.
Police told the (Sydney) Telegraph that is when the dog ran to its owner.
"At the moment she pulled the trigger, her dog jumped on her and diverted the shot," a local officer said. The dog "probably sensed things and knocked into her to save her."
The woman was unconscious when her husband found her. He then called paramedics, who treated her for nonlife-threatening injuries.
This isn't the first time recently that a dog has been deemed a hero.
Three days ago, a toddler named Julia, from Poland, was saved by a stray dog, who firefighters said prevented the girl from freezing to death after she wandered from her home during the night.
Several reports said the three-year-old girl is believed to have walked to a forest near her home in the village of Pierzwin, as temperatures reached below zero.
More than 200 people searched for the girl before firefighters finally found her crying for her mother. It wasn't clear how Julia became separated from her parents, whose names weren't immediately available.
Grzegorz Szymanski, one of the firefighters who found the little girl, said that if it hadn't been for the dog, she likely wouldn't have survived.
“For the whole night the animal was with the girl, it never left her. Remember, it was five degrees below zero and the child was wet," he told BBC. “This dog is the most important part of this story, he is a hero. It is thanks to this dog that the girl survived the night."