Hamer is a woreda in South Ethiopia Regional State.
Part of the Debub Omo Zone, Hamer is bordered to the south by Dasenech woreda, to the southwest by Kuraz, to the west by Nyangatom, to the north by Bena Tsemay, and to the east by the Oromia Region; the Weito River separates it from the Oromia Region.
Hamer includes part of Lake Chew Bahir along its southeastern border.
The administrative center is Dimeka; other towns include Turmi.
The majority of the inhabitants practiced traditional beliefs, with 91.32% of the population reporting that belief, 3.02% practiced Ethiopian Orthodox Christianity, 2.4% were Protestants, and 2.09% were Muslim.