A peaceful protest was also staged in Christchurch, where spokesman Dan Rae said 400-500 people attended.
Another protest in Auckland resulted in one arrest.
In Dunedin's Octagon about 100 protesters heard speakers from several organisations.
People were given red arm bands to symbolise blood and suffering in Gaza.
They carried placards calling for an end to the war.
Otago Muslim Association minister Gamal Fouda said what was happening in Gaza was "shameful" and a "brutal massacre".
Prayers were led, messages of support read and the Government urged to do what it could to end the conflict.
Tenoch King, a member of the public who asked to speak, said she was a Jew and not all Jews supported what was happening in Gaza.
Across the Octagon, a small group of Israeli supporters held up a banner and Israeli flag in support of its country.
Yonatan Frank, one of several Israeli tourists, said they came to support their country, which was only defending itself.
Global Peace and Justice group spokesman Mike Treen said the Auckland protest was outside the headquarters of Rakon, a technology company that makes crystal oscillators for Israeli bombs.
The demonstration was largely peaceful, although red paint bombs were thrown and a man was arrested for painting "kills" on the building.
A march on Parliament is planned for tomorrow, with protesters asked to bring or make a key as a symbol of "Palestinian dispossession". - with NZPA
