It has brought a contingent of 21 medical personnel that includes a surgeon, an anesthetist, nurses and a scientist.
The contingent is aboard the HMNZS Canterbury as part of Exercise Tropic Major.
It is the first time the Canterbury's operating theatre and laboratory have been fully operational.
With an intensive care unit, x-ray, ultra-sound facilities and a blood bank, the contingent is capable of performing operations and trauma care.
Its officer in charge, Bronny Clulow, who is a registered nurse, said the contingent was a mixture of reservists and regular forces.
While in Vanuatu the New Zealand Defence Force (NZDF) is delivering more than 50 tonnes of relief supplies for people affected by the eruption on Ambae Island.
The offshore patrol vessel HMNZS Wellington is also involved in Exercise Tropic Major.
The NZDF said the aim of the exercise was to give its personnel practice operating in a joint task force in a tropical environment, providing regional security and development assistance.
The exercise involves a fictitious scenario in which law and order has broken down on Epi Island, prompting the Vanuatu government to request help to re-establish the rule of law and stability for its citizens.
Training for members of the Vanuatu Police Force would also be provided.
Photo NZ Navy