Hore was cited on Sunday evening for allegedly striking Wales lock Bradley Davies during the opening exchanges of the All Blacks' 33-10 win in Cardiff.
Davies was laid out by a punch from behind by Hore and the Cardiff Blues lock later went to hospital to undergo precautionary checks.
A Six Nations Committee statement said: "Andrew Hore, hooker for New Zealand, has been cited by the IRB's independent Citing Commissioner for allegedly striking an opponent during the match between Wales and New Zealand at the Millennium Stadium on Saturday.
"The relevant incident occurred in the second minute of the match and involved Wales lock forward Bradley Davies.
"The time and date of the hearing, before the IRB's appointed independent judicial officer, have yet to be fixed."
Neither referee Craig Joubert nor his assistants saw the ugly incident, but New Zealand coach Steve Hansen had conceded he expected Hore to be cited.
Wales coach Warren Gatland was left distinctly unimpressed by Hore's actions, and said: "It does not look the best in the world. It looks like he (Davies) has been caught from behind.
"You do not associate the All Blacks as being a side that resort to cheap shots, and I hope that is not the case and that maybe it was an accident.
"Bradley was a big loss to us and it took us a bit of time to cope."
New Zealand had called Chiefs hooker Hika Elliot into their squad in anticipation of Hore's citing.
And with Mealamu struggling with a calf problem ahead of next weekend's meeting with England at Twickenham, Hansen may be forced to select Dane Coles and Elliot, who between them have just five caps, among his 23 for their tour finale.
Crusaders fly-half Tom Taylor, son of 1987 World Cup winner Warwick, also joined the All Blacks squad with Dan Carter nursing the Achilles injury that forced him to withdraw from the side to face Wales.
Carter was injured during training last Thursday, and the fact that Taylor has been called up as cover suggests he could be struggling to make the encounter with England as the All Blacks look to end 2012 by extending their unbeaten run to 21 Tests.