Others expressed concern about how Hanson's election success had sparked attacks against Muslims.
More than 14,000 people tweeted 71,000 times using the #QandA hashtag during the programme, according to the ABC.
Twitter lit up during an exchange between Hanson and Labor Senator Sam Dastyari, who migrated to Australia with his family in 1988 from Iran.
Dastyari asked if Hanson would have allowed him into the country as a 5-year-old because he was born Muslim.
"Are you a Muslim?" Hanson asked. "I'm surprised, I didn't know that about you."
Hanson's reaction drew bewildered laughs from the live audience. "It is a matter of real concern that a member of our Senate is so foolish," prominent Australian barrister Julian Burnside tweeted.
Hanson did draw support from some. One tweeter who went by the name of Grandee Zip described Hanson as a strong Australian woman who was "defending our rights" and "shining light on unfolding catastrophe".
Hanson says she's had a flood of support since appearing on the programme. "People are just saying 'please don't give up, you are there as a voice for us'. This is not an issue I'll allow to be buried under the carpet," the One Nation leader said. "You hear the Prime Minister going on about border protection. But this is within our borders now. This is our greatest danger."
- AAP
