A neo-Nazi poster urging people to gun down gay and transgender people has been plastered on Swinburne University's walls, raising fears the toxic homophobic campaign was triggered by the plebiscite debate.

Students arriving at the university's Hawthorn campus on Monday morning were confronted with an illustration of a skeletal man wearing a T-shirt reading "Gay and Proud", with a bullet through his head. The poster, which included a swastika, was titled "Get the sodomite filth off our streets".

A neo-Nazi homophobic poster that circulated at Swinburne University.

Fairfax Media has chosen not to name the people behind the poster. They claim to belong to an organisation that has no online history. This could be the work of as few as one person.

The posters were stuck onto the university's walls on the day of an annual gay pride event, which included a pride march and a speaking session featuring former High Court judge Michael Kirby and Victoria's Gender and Sexuality Commissioner Rowena Allen.