Of the 17 alleged victims 14 were sexually abused and others were subjected to physical abuse.
Police allege one boy was allegedly assaulted with a bamboo stick.
It is alleged that some boys placed in the man's care sustained multiple sexual assaults over a number of weeks or months.
The man is also accused of threatening to kill other boys and supplying methamphetamine and cannabis to youngsters.
It is understood police have not ruled out further charges - and as the investigation is ongoing, further complainants may be identified.
Child Youth and Family - now Oranga Tamariki - are understood to be investigating the situation.
Police could not comment on the matter as it is before the courts.