O'Connor also questioned Ardern on the topic at this morning's Newstalk ZB leader's breakfast.
Ardern said O'Connor was conflating suicide with euthanasia which she did not agree with.
She believed people should be able to make their own decisions when it came to euthanasia, but it was a conscience issue and O'Connor held his own views.
"I don't draw that same comparison at all, the 600 people in New Zealand who have taken their own lives, will shock and appal all New Zealanders, the fact our mental health services aren't doing enough for those people that's something we should be talking about."
She said people having the ability to make the choice about their own end of life, if they have a terminal issue, was "absolutely" a different issue.
"I have said openly that I believe people should be able to make their own choices in those circumstances, O'Connor disagrees...that's a conscience vote for us all."
Earlier this year O'Connor chaired a parliamentary health committee on the issue of assisted dying which made no recommendations to change the current law.
Many responded to the MP's initial post on Facebook with at least 205 "angry faces" compared to 162 likes and 12 hearts in apparent support of the post.
One woman described O'Conner has having a "breath-taking" level of ignorance.
"A ridiculous comment...aligning youth suicide with the sick and elderly's right to die a dignified death. Your ignorance is breathtaking [sic]."
One woman, a self-proclaimed National supporter, said she could not agree with his views and was contemplating voting for another MP as a result of his comment.
"I believe in assisted dying with stringent rules like overseas have - you should never have been on the committee that looked at assisted dying as you were already biased given your religious views. I'm not religious but understand that everyone has a right to believe what they want.
"However, when it comes to politics you can't let your personal views get in the way of helping to move the country forward."
O'Connor responded to the comment, by saying there was no such thing as stringent safeguards.
Not all were in opposition to his statement, with one man saying "a life is a life".
Another woman commented she was in total agreement. "Stay strong on this one! Euthanasia is certainly assisted suicide. More importantly legalising it will set a dangerous precedent. We have seen with some countries, the extension of euthanasia on mentally-ill people."
Where to get help
If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call police immediately on 111.
OR IF YOU NEED TO TALK TO SOMEONE ELSE:
• LIFELINE: 0800 543 354 (available 24/7)
• SUICIDE CRISIS HELPLINE: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• YOUTHLINE: 0800 376 633
• NEED TO TALK? Free call or text 1737 (available 24/7)
• KIDSLINE: 0800 543 754 (available 24/7)
• WHATSUP: 0800 942 8787 (1pm to 11pm)
• DEPRESSION HELPLINE: 0800 111 757
