Despite the grim statistics, there was a ray of hope in South Africa, where the killings decreased slightly for the first time in years.
South Africa showed some improvement after aggressive anti-poaching efforts, but the overall number of rhinos killed increased in other nations.
"This is testimony to the valiant and enormous efforts underway -- often against overwhelming odds -- to curb the losses," said Inger Andersen, director general of International Union for the Conservation of Nature, which compiled the data.
"Sadly, these improvements have been dampened by alarming increases in poaching over the past year in other vitally important range states, such as Namibia and Zimbabwe."
South Africa is home to about 80% of Africa's rhinos, making it a crucial conservation hub for the iconic animal.
Crime networks join in
The killing of the animal has increased in recent years, fueled by a growing belief in Asia that its horns purportedly cure cancer.
As clients in countries such as China and Vietnam pay top dollar for rhino horns, poachers are getting brutal and sophisticated.
The demand has attracted global crime networks, complicating conservation efforts.
"The extensive poaching for the illegal trade in horn continues to undermine the rhino conservation successes made in Africa over the last two decades," said Mike Knight, chairman of African rhino specialists for the International Union for the Conservation of Nature.
Threatened species
Pressure is growing to protect the second-largest land mammal after the elephant.
The northern subspecies is believed to be extinct in the wild, according to the World Wildlife Fund, while the "near threatened" southern white rhino population is growing in sanctuaries.