Independent Member for Kooyong Monique Ryan has reported to police that several of her supporters have received "misogynistic, racist and threatening" letters since the election.
The newly elected federal MP said her office had spoken to both the Australian Federal Police and Victoria Police and urged anyone who had found the handwritten, anonymous letters in their mailbox to contact their local police station.
"In recent days, several more of these anonymous letters have been placed in supporters' mailboxes," she said, in a statement released on Monday evening.
"Their contents are misogynistic, racist and threatening.
"It is extremely disappointing that people are being targeted for exercising their democratic rights.
"These cowardly anonymous threats are very distressing for the people who receive them."
The Melburnite said she and her staff would help anyone who received one of the threatening anonymous letters.
"Our advice from the Australian Federal Police to anyone who receives a letter like this is to immediately contact Victoria Police and give them the letter and any relevant security camera footage, if available," Ryan said.
The AFP said it did not comment on "matters that may be the subject of investigation".
A Victoria Police spokesperson said they couldn't confirm whether the matter had been reported to the police without more information about when and where the complaints were made.
Ryan beat former treasurer Josh Frydenberg in May's election, taking the seat out of Liberal hands for the first time in decades.