The man involved was not an on-air personality or a member of the broadcast company's management team.
The incident comes after a former TVNZ employee spoke out earlier this week and alleged she was sexually assaulted by a drunken senior manager.
Andi Brotherston, a spokeswoman for the broadcaster until her departure in 2011, shared an incident from 2010 in which the senior manager organised a lunch before cancelling all the attendees except for her.
"He started sculling Peronis and kept telling me to keep up with him ... all the while asking me why I never wore low cut or tight tops," she said.
"I went to the loo, he followed me in, pinned me against the wall and started trying to grope/kiss me and said he'd booked a motel room across the road. Thankfully I was able to shake him off. I ran out of the restaurant, down Parnell Rise and into a taxi."
She then decided to make a complaint to a member of TVNZ's HR department - a woman - but was shocked at the response.
Brotherston said the HR person laughed at her and said no one would believe her.
"I got up and walked out," she said.
"I tweeted that because this still happens every day."
She said she was disappointed that it wasn't taken seriously.
In response, a TVNZ spokeswoman said the company was "saddened" to hear about the "completely unacceptable harassment behaviour at TVNZ back in 2010".
"It takes courage to step forward and openly talk about experiences like this and we respect Andi for doing so. She has the right to be heard, and we have a responsibility to listen and reflect on what she has to tell us about her time at TVNZ.
"This is a matter we take very seriously. We have zero tolerance for any form of harassment in our workplace and we're committed to providing a working environment that is inclusive and respectful."
The spokeswoman said the manager no longer worked at TVNZ.
TVNZ chief executive officer Kevin Kenrick also made a public statement inviting others to come forward.
He said the company wanted to hear from anyone who had experienced similar incidents.
"We think that there is an opportunity to learn from that and where appropriate to apologise for behaviour that was unacceptable," he said.
A TVNZ spokesperson said it fully supports the decision of those who wish to take a stand and publicly share their personal story.
"We respect it's their choice about what they choose to disclose and to whom and we'll only talk to external media with their express consent."