He didn't address the controversy in his speech to delegates, but criticised "myths" around suicide.
"Forty per cent of our kids in school will have a suicidal thought - whether it is a one-off fleeting thought or a recurring thought that grinds them down on a daily basis.
"It is a normal part of being a human being...but such is the strength of the S word and the myths that surround the S word we have made it wrong for young people - we are told that you can't think of the S word. Telling people how to think is completely stupid."
King said mental health support and suicide prevention shouldn't be lumped together, and said New Zealand's mental health system was "broken" and a stocktake of services was badly needed.
"Do we need more money in the system? Who knows...we are currently refusing to do a stocktake of mental health services...we are all saying, what are you hiding?
"Ten years ago you could walk into a hospital and say, 'I am feeling suicidal I need help' and the help was there. Nowadays you have to prove that you are suicidal. You have to actually make a serious attempt on your own life to get the help you need. What kind of system is it that you need to attempt suicide to get help?"
King, who received a standing ovation from delegates after his speech, also criticised the effort to link New Zealand's suicide rate with other problems such as inequality and racism, and said much of it boiled down to the strength of family support.
Delegates are continuing to debate policy remits today. If successful, the remits will go to the party's MPs for debate on whether they should be adopted as policy.
After strong debate delegates supported a remit from the Wellington Central branch for NZ First to support a universal child allowance payable to every child 16 and under.
MP Tracey Martin spoke in favour of the remit, saying she had run the numbers and the policy was affordable, and would use funding already allocated through Working for Families.
"What this says is we will support our children, regardless of where they are, we will support them."
Winston Peters will give his keynote speech later today.
Yesterday he told media that economic conditions were putting strain on New Zealanders, particularly farmers, and Fonterra needed to be asked how many farmers it expects will commit suicide this year.
"A whole lot of farmers out there are hard against the wall and suicide is what a lot of them will do," Peters said.
The New Zealand Herald is running a special series on youth suicide called Break The Silence. It aims to raise awareness of our suicide rates, to start a national conversation about the issue and to encourage young people to ask for help.
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 111.
If you need to talk to someone, the following free helplines operate 24/7:
DEPRESSION HELPLINE: 0800 111 757
LIFELINE: 0800 543 354
NEED TO TALK? Call or text 1737
SAMARITANS: 0800 726 666
YOUTHLINE: 0800 376 633 or text 234
There are lots of places to get support. For others, click here.
