About 1500 visitors from throughout the South Island and further afield are expected in the city in November for the Hui-a-Iwi from November 20 to 22.
The three Otago runanga - Otakou, Puketeraki and Moeraki - will jointly host Te Runanga o Ngai Tahu's biennial hui for the first time.
The event would be a three-day celebration of Ngai Tahu culture in the city, Te Runanga o Ngai Tahu event co-ordinator Kitty Brown said.
It would also be an opportunity for Dunedin to be promoted to delegates from Christchurch, Kaikoura, Southland, the West Coast and Australia.
Enterprise Dunedin director John Christie said the conference would be worth hundreds of thousands of dollars to the city's economy over the three days.
''It certainly is a significant event for the city, both culturally and in the number of people it'll be bringing into the city,'' he said.
''It brings significant economic benefits.
''They are significant numbers [1500 delegates]. That's a big delegation of people to come to the city.''
Based on figures submitted by Enterprise Dunedin in a report to the Dunedin City Council economic development committee earlier this month, the event could be worth more than $2 million to the city.
Dunedin Mayor Dave Cull said he was excited by the event.
''I'm always pleased when a big conference comes to Dunedin but I'm particularly pleased it's Ngai Tahu,'' he said.
''Ngai Tahu is the South Island runanga and it's great that they are holding their event in our city.''
He was enthusiastic about the cultural impact of the event on the city.
''There's an economic significance and in this, being Ngai Tahu, there's a cultural significance,'' he said.
''Council has a very good and close relationship with the Ngai Tahu runanga in our area, and it will be great to welcome their wider whanau.
''It's great to be able to show off the city.''
He would personally welcome the delegates to the city if he was in town during the event, he said.
Mrs Brown said the event would act as Ngai Tahu's annual meeting.
The public would be welcome to attend on Saturday, November 21, at the Dunedin Town Hall as the iwi showcased its culture to Dunedin's residents, she said.
''We have a huge programme of workshops [on Saturday], from flax weaving to tribal economics to presentations on migration theory.''
Harrop St would be closed and filled with arts, crafts and kai stalls, she said.
Busloads of iwi members would be transported around Dunedin during the weekend to visit the city's museums and other cultural highlights, such as the Hocken Library and Dunedin Public Art Gallery, Mrs Brown said.
''We want to bring the community in and show what Ngai Tahu is up to and what it does, but at the same time the local runanga want to take the opportunity, while so many Ngai Tahu are in town, to showcase the city.''
Paulette Tamati-Elliffe, of Te Runanga o Otakou, said the local runanga were excited to host the hui for the first time.
''There will be something for everyone,'' she said.
''It's a festival to celebrate Ngai Tahu culture and for those who have not engaged with the iwi that much, it will give them an idea of what we are about - an opportunity to make connections.''
