Maori King Tuheitia Paki says he is deeply shocked and disappointed at comments posted by his son on his Facebook page.
Korotangi Paki recently pleaded guilty to two burglary charges and one of theft from a car, and an earlier charge of drink-driving. He was this week discharged without conviction - an move criticised by some.
The 18-year-old made the racist comments on Facebook last year, including one of photo of Asians in a queue at an airport with the label "chingy eyed".
In another post, he signed off a comment with "seig heil" - the Mongrel Mob's misspelled adoption of the Nazi slogan.
The Facebook photos and accompanying comments posted by him have been published on the Radio Live website.
In a statement, King Tuheitia said that he apologised unreservedly for any offence the comments had caused and had let his son know of his extreme displeasure.
He said he did not condone racism in any shape or form, and that the ill-advised use of a gang slogan could be put down to the "ignorance of youth".
The Facebook account has been disabled.
Labour Party MP Nanaia Mahuta, who is Korotangi Paki's aunt, said the comments were unacceptable.
They did not send the right signals to young people about what was acceptable in a society such as New Zealand's, where people were treated fairly, equally and with respect, she said.