The appeal comes in a joint statement from the UN human rights chief Louise Arbour and the head of the UN refugee agency, Antonio Guterres.
Hundreds of Uzbeks fled to Kyrgyzstan after Uzbek troops fired on protesters in the nearby eastern town of Andijon on 14 May.
In the statement, Arbour said Uzbek asylum seekers could face human rights violations -- including torture and summary execution -- if sent back to Uzbekistan.
In another statement, UN Secretary-General Kofi Annan called on Kyrgyzstan to abide by its international obligations, saying forced deportations violate the 1951 UN Refugee Convention. Kyrgyzstan is a signatory to the treaty.
On 22 June, the U.S. rights groups Freedom House also urged Kyrgyz officials not to send home Uzbek refugees.
Its director in Kyrgyzstan, Stuart Kahn, told RFE/RL that Kyrgyz authorities did not know what potentially awaited Uzbek refugees back home.
"The response from the [Kyrgyz] authorities, really, is that there are a lot of considerations to be taken into account [regarding deportations]: Kyrgyz law, their covenants under CIS agreements, as well as international covenants," Khan said. "And they are using this variety of agreements to justify the return of the Uzbeks, despite really knowing what fate may await them."
The appeals come on the same day that Uzbek authorities requested Kyrgyzstan send back 133 Uzbeks suspected of involvement in the unrest in Andijon.
(AP)For more on these events, see RFE/RL's dedicated webpage: Unrest in Uzbekistan