A married senator sexually harassed at least six staff in his office in this term of parliament, Pauline Hanson claims.

The One Nation leader used parliamentary privilege to accuse an unnamed senator of harassing the women, and alleged taxpayer funds were used for payouts to keep some of them silent.

"This gutless wonder we call senator should hang his head in shame," Senator Hanson told the upper house on Tuesday night.

"I rise tonight to share my disappointment at another case of serious sexual harassment by a current senator that is currently under investigation - a married senator," she said.

Ms Hanson said six of the unnamed senator's staffers have been "gagged from speaking publicly about their experience".

"I expect the behaviour of all elected members to be honourable. What senators in this place need to understand is that our staff are no different to us. Just because you wear the red pin doesn't give you permission to place your unwanted hands or lips on your staff."