The memorandum of understanding was signed on Wednesday by Queenstown Mayor Vanessa van Uden, Destination Queenstown chairman Mark Quickfall and Ulsan Metropolitan City deputy mayor Dong-Ho Oh.
Ulsan, which is in mountainous terrain, has a population of 1.2 million and is home to car-maker Hyundai.
The South Korean delegation visited the Queenstown cycleway and was given an overview of the trail's funding by council community services manager Paul Wilson.
Ulsan's deputy mayor told councillors New Zealand was a "people-first" country, which the Republic of Korea emulated.
Before the understanding was signed, Ms van Uden said she looked forward to a "long and fruitful relationship" with the city of Ulsan "on behalf of Queenstown" and joked that despite the similarities, the resort did not have any car-manufacturing plants.
According to the understanding, the parties agreed to "jointly co-operate in promoting mountain tourism and attracting mountain tourists at a global level in order to invigorate the sustainable mountain tourism of both destinations".
