Namibia said the buffalo meat would be donated to the local community and carcasses were being collected.
More than 400 buffaloes believed to have been chased by lions drowned in a river in northern Botswana this week, the government said.
The mass drowning occurred on Tuesday night in Chobe River on the border with Namibia.
Investigations by authorities in both countries "suggest that an exceptionally large buffalo herd was grazing in Namibia when they stampeded into the Chobe River," Botswana's Ministry of Environment, Natural Resources Conservation and Tourism said in a statement late Wednesday.
"Initial indications are that they were being chased by a pride of lions," it said.