"The court's interpretation of the relevant copyright provisions cannot be right.
"The precedent set is concerning and has ramifications in New Zealand outside my case."
Dotcom said he was "prepared to fight to get justice".
"I will appeal to the Supreme Court. Just yesterday, the United States accepted that right exists. My legal team are confident that the Supreme Court will hear the appeal given there are such significant legal issues at stake.
"Many important cases in New Zealand are not won in the Court of Appeal, or in the courts below, but are won when they reach the Supreme Court. My case will be one of those."
The ruling comes just a few months after the German multi-millionaire moved from Auckland to Queenstown to start a new life with wife Liz and his five children.
Speaking to the Otago Daily Times from his mansion on the outskirts of the resort in May, Dotcom said he was still optimistic about his case, but admitted there were times he worried about the outcome.
"I knew that I had done nothing wrong. I knew that I was dealing with things according to the law. We always had high-paid lawyers giving us advice.
"I never again, after my youthful indiscretions with the law, wanted to be in another situation like that so I had good legal advice.
"So I would say the vast majority of the time I was quite positive. The only problem about this case, and that is the big unknown, is the political nature of it."
The Dotcoms had said they wanted to stay in Queenstown for the long haul.
Dotcom already had his eye on business opportunities, from real estate investments to a luxury cinema.
A US grand jury indicted Dotcom, Mathias Ortmann, Bram van der Kolk and Finn Batato on February 6, 2012, over the now-defunct file-sharing website Megaupload, which allegedly shared pirated films and other media.
It followed the now-infamous armed raid on his Auckland home on January 20, 2012.
The US has sought the men's extradition ever since.
Yesterday's ruling also stated Ortmann, van der Kolk, and Batato can be extradited.
The group lost their case in the North Shore District Court in 2015 and have now lost appeals to the High Court and the Court of Appeal.
The group can seek leave to appeal the Court of Appeal's judgement to the Supreme Court.
If that fails, the final decision as to whether Dotcom and the other men will be extradited rests with Justice Minister Andrew Little.
The Appeal Court Justices - Stephen Kos, Christine French and Forrie Miller - found the extradition pathways the US relied on were available to the US, and it had "tendered sufficient evidence to support their case on those pathways".
In an FBI-ordered raid in 2012, police used the anti-terrorist Special Tactics Group in a helicopter assault on Dotcom's former Coatesville mansion.
Police are believed to have paid Dotcom a six-figure sum last year, in a private settlement over alleged unreasonable force.
