Exercise Barrier 2012 will take place over eight weeks, running until late June.
It will start from first notification that a vessel is on the way, through to processing and accommodating the asylum seekers while their claims are determined.
The drill will include several planning exercises and a simulated mass arrival at Devonport Naval Base in June.
The New Zealand Customs Service and Immigration New Zealand will be the lead agencies for the exercise.
Other agencies involved include Defence, Police, Health, MAF, Foreign Affairs and Trade, Corrections and Social Development.
"Agencies continually monitor the risk of a mass arrival and ensure plans to respond to such a threat are up to date. This exercise will help agencies test their planning at a practical level,'' said Mr Guy.
"Together with the new legislation we are introducing, this sends a strong message that queue jumpers and people smugglers won't be tolerated.''
The law change, announced today, means groups of asylum seekers, such as boat people, will be detained as a group rather than under individual warrants as currently happens.
It will take longer to get permanent residence _ a claimant's refugee status will be reassessed three years after it is first decided and permanent residence will not be granted until that happens.
Those who do get residence will be able to sponsor only their immediate family members to follow them to New Zealand, rather than extended family.
Mr Guy said the changes were not aimed at punishing people with a genuine claim for refugee status, and New Zealand remained committed to its obligations, under which it has an annual quota of accepting 750 people who have been deemed refugees by the United Nations High Commissioner for Refugees.
"There are appropriate channels for genuine refugees to use. We cannot start accepting boat loads of people - we need to deter them before they take to the sea.''