Hundreds of thousands people were affected by the operation which began May 18 and ended in late July.
Shacks, homes and small businesses were razed in shantytowns and other poor urban areas.
The government has portrayed the cleanup blitz as an urban renewal campaign and said it would build new housing for the displaced.
Mr Egeland said the evicted slum dwellers had gone back to live with relatives in the countryside or had gone to other urban slums.
Many are still drifting around, sleeping outdoors and living in overcrowded urban shelters he said.
The largest group lives in Hopley Farm near Harare, where at least 4,000 to 5,000 people endure rudimentary conditions, he added.
Mr Egeland noted that the demolition campaign could not have come at a worse time for Zimbabwe, which is being blighted by the effects of AIDS, food insecurity and crumbling basic services.
“Life expectancy has plummeted from around 63 years in later 1980’s and early 1990’s to 33.9 years in 2004… this is a meltdown,” he lamented.
A quarter of the country’s population is infected by the AIDS virus, with 3,000 people dying from the disease per week and 1.3 million children orphaned, he noted.
“Food insecurity is also now very severe and growing in Zimbabwe,” he said.
Egeland said that following a US$11.9 million (A$15.7 million) appeal
launched by his office a big humanitarian program has been undertaken to reach up to 200,000 people.
But he said the Harare government was refusing to cooperate with a larger UN program to assist those hardest hit by the eviction campaign, including a plan to resettle affected slum-dwellers.
“We have not reached agreement with the government .. (on) how many are affected, how to help them, the role of (non-governmental organizations) and other operational aspects,” he said.
“We will continue our dialogue with the government,” he noted. “We are working hard to gain access to people in need and to get donors’ funding.”
Mr Egeland said the World Food Program was already feeding one million people in Zimbabwe and was making preparations to feed 2.9 million people before the end of the year.