The Defence Minister has ordered an internal review of the way the defence force treats women.
Jonathan Coleman says he has asked for the review following revelations of harassment in forces overseas, including Australia.
The number of women in the New Zealand army has gradually dropped since 1995, from 17% of the total to 13%.
Dr Coleman says even women in the military who are very supportive of the defence force say they have found it harder to advance because they are female.
He says he would be shocked if the review found systemic harassment but would take immediate action if that proved to be the case.
Army deputy chief Brigadier Peter Kelly says it would be naive to think there is no sexual discrimination or harassment going on in New Zealand.
He says not all of it may be reported so the defence force does not know the exact extent.
Brigadier Kelly says he is concerned by a gradual drop in the proportion of women in the army and there is work to do in that regard.
Dr Coleman says he expects the review to be completed within weeks.
