The five-strong delegation will meet both President Robert Mugabe and Prime Minister Morgan Tsvangirai during their five-day visit, delegation spokesperson John Nyaga said.
On Sunday the team, which is led by UN assistant secretary general for humanitarian affairs Catherine Bragg, will hold an "internal meeting with UN officials working on the ground in Zimbabwe," Nyaga said.
"The aim of the mission is to understand the reality of the situation in Zimbabwe," he added.
The team, which also includes representatives from the World Health Organisation (WHO), World Food Programme (WFP) and the UN Children’s Fund UNICEF, will on Monday visit different project, mainly in the capital Harare.
Mugabe, who turned 85 on Saturday, agreed to allow the top-level UN team to visit Zimbabwe to find ways of dealing with the country’s growing health and food crisis, UN chief Ban Ki-moon said earlier this month.
The delegation flew in late on Saturday.
According to figures released Saturday by the World Health Organisation and Zimbabwe’s health ministry, the latest death toll from the cholera epidemic was 3 806, with more than 81 000 cases reported.
At the same time, seven million people – more than half the country’s 12-million population – need emergency food aid, according to UN figures.
The country is also struggling with the effects of an economic meltdown that has left it with the world’s highest inflation rate: officially 231 million percent in July, though believed to be much higher.
South African President Kgalema Motlanthe, chairperson of the Southern African Development Community (SADC) has convened the body’s finance ministers this week to devise a plan to help them out of the crisis.
On Friday, Tsvangirai said that reconstructing Zimbabwe could cost as much as $5bn after a meeting with Motlanthe on Friday in Cape Town.