"New Zealanders should be security conscious at all times and be extra vigilant in crowded or landmark places as well as proximity to hotels, bars, shopping areas, and tourist resorts."
Jerusalem's tourist areas should be avoided as should public transport facilities, the ministry said.
It warned that the law and order situation in Papua New Guinea continued to pose risks to travellers.
Tensions between ethnic or clan groups sometimes led to outbreaks of tribal fighting, often involving firearms.
Crime rates were high in Port Moresby and other urban centres.
"Assault, armed robbery and sexual assault, including gang rape, continue to occur. Robberies including inside shops and restaurants are common in Port Moresby and other urban centres.
"We reiterate that New Zealanders in Papua New Guinea should exercise a high level of personal security and vigilance at all times, especially in public places and areas frequented by foreigners."
New Zealanders wanting to travel to Bougainville should discuss their plans with the New Zealand High Commission before setting out.
- NZPA