Thousands of university and high school students joined co-ordinated rallies in every major city and several regional centres on Thursday.
The rallies followed a similar national walkout in August.
In Sydney, well over 1000 people gathered for a Students Say No To Hanson rally, with attendees carrying a large paper mache head depicting the One Nation leader's likeness.
Chants of "Pauline Hanson go to hell, take your racists there as well" filled the air as the crowd marched from Hyde Park to Sydney Town Hall.
High school students, some dressed in uniform, held placards reading: 'One Nation? I don't like it' and 'Highschoolers against Hanson'.
Protest organiser Yasmine Johnson said Senator Hanson's latest policy interventions against immigrants and international student visa holders left many in the student community afraid for their future.
"One of the first groups Pauline is saying she will come for is international students ... for uni students it will mean the total destruction of life as we know it at university," the 26-year-old University of Technology Sydney student told AAP.
"There's a huge section of our community who are migrants or international students ... students can look around and see they live in a society full of migrants and they want to defend their future."
In Melbourne, hundreds of students gathered outside Victoria's State Library carrying anti-One Nation signs before marching through the city streets.
One Brisbane protester brought a sign reading "Hanson is a primitive species", in an apparent response to Ms Hanson's qualified apology for past comments labelling Indigenous Australians "the most primitive race on Earth".
Similar messages were heralded across Adelaide and Hobart's Parliament House.
A central theme for many protesters throughout the day was One Nation's migration policy, which promises to lower immigrant numbers by hundreds of thousands.
The party plans to reduce the number of temporary visa holders and overstayers by more than 750,000 over three years.
International student visas would bear the brunt of the cuts, with visa grants set to be reduced from more than 290,000 to 115,000 per year and secondary visas for family members eliminated.
