Aaron Pennell, 36, of Owen Street, pleaded guilty in Warrnambool Magistrates Court on Tuesday to making threats to kill and making threats to destroy property.

The charges related to an incident on April 6 when Pennell and the victim began arguing about the man going out the night before with his friends.

Pennell became infuriated and started yelling at the victim who threatened to call the police.

The man threatened the victim, stating he would shoot her in the head with a 12 gauge shotgun.

The victim told police she feared for her life.

Pennell was arrested a property in Warrnambool's Banyan Street about 7am last Tuesday.

He was conveyed to Warrnambool police station where a search uncovered 17 strips of Suboxone - a prescription medication used to treat opioid addiction.

Pennell made a no comment interview.

Lawyer Jess Dean said her client had 18 pages of criminal history.

"And while it is lengthy, I would note that there is minimal history of violent offending," she said.

"The last (violent-related offence) was in 2005."

Ms Dean said the offending did not include a physical assault and Pennell had no intention to follow through with the threat.

Magistrate Mark Stratmann fined the man $1500.

"If it had gone further I frankly would have put you in jail," he said.

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