Ministry of Foreign Affairs and Trade spokeswoman said the embassy was in touch with local authorities to see in any New Zealanders had been involved.
"At this stage we are not aware of any New Zealanders who have been affected or seeking assistance," the spokeswoman said.
There are currently 39 New Zealanders registered on SafeTravel as being in Seoul.
Two foreigners were among the dead, officials said.
At a media briefing at the scene, head of the Yongsan Fire Station Choi Sung-beom said a further 150 people were injured in the commotion in Seoul's Itaewon district.
Nineteen of the injured were in serious condition and receiving emergency treatment, and officials said the death toll could rise.
He said 74 of the dead had been sent to hospitals while the bodies of the remaining victims who had been kept on the streets were being transported to a nearby gym so workers could identify them.
This was the first Halloween event in Seoul in three years after the country lifted Covid-19 restrictions and social distancing.
Many of the partygoers were wearing masks and Halloween costumes, and witnesses were quoted in reports saying the crowd became increasingly unruly and agitated as the evening deepened.
Officials say people were crushed to death after a large crowd began pushing forward in a narrow alley near Hamilton Hotel, a major party spot in Seoul.
The stampede happened around 10.20pm, and many of the victims were women in their twenties, Choi said.
"A number of people fell during a Halloween festival, and we have a large number of casualties," Choi said.
Footage on social media showed hundreds of people packed in the narrow, sloped alley crushed and immobile as emergency officials and police tried to pull them free.
The Itaewon district is popular with young South Koreans and expatriates alike and is known for its nightlife.
Its dozens of bars and restaurants packed on Saturday for Halloween after businesses had suffered a sharp decline over three years of the pandemic.
More than 800 emergency workers and police officers from around the nation, including all available personnel in Seoul, were deployed to the streets to treat the injured.
The National Fire Agency separately said in a statement that officials were still trying to determine the exact number of emergency patients.
