The East Coast tribe presented a report into its iwi-led model of care to the Children's Commissioner and the Ministry of Social Development.
It said the current Memorandum of Understanding signed in 2013 between the iwi and the Crown was not a partnership based on the Treaty of Waitangi.
Between 2015 and 2017, there was a 38 percent increase in the number of Ngāti Porou tamariki going into state care, up to 425.
A spokesperson said the iwi would be presenting a business case to get more resources from the government, to increase its social services.