The appointment marks the first time the tourist body has selected a global media agency.
In the UK, MindShare pitched against the incumbent, Walker Media, and Media Planning Group to secure the £3m business.
MindShare will also work with Tourism New Zealand in its key markets of the US, Australia and Japan.
Tourism New Zealand chief executive George Hickton said: 'The appointment of MindShare across all our markets will ensure greater consistency in the delivery of our brand message across the world.'
The tourism body's ad account is with JWT and New Zealand agency Assignment Group, which won the work earlier this year.