Yes you can. Here's what the government says:
https://www.govt.nz/browse/nz-passpo...name/#overview
You can change your own name in New Zealand if you're over 18 and a citizen or permanent resident.
You can apply to change your name if:
you're 18 or over, and
you were born here or are an NZ citizen, or you're entitled to live here indefinitely (you're a permanent resident of NZ or Australia, or you're Australian)
You don't usually need to apply for a name change if you've taken your partner's surname after marriage or a civil union, or if you want to use your birth surname (maiden name) again after a divorce.
https://www.govt.nz/browse/family-an...u-get-married/
In New Zealand, you don’t usually have to do anything special if you want to change your name after you get married or have a civil union.
When you get married, you can:
keep your last name
take your husband, wife or partner's last name
hyphenate or use a combination of both your last names. ...