A government statement said Dlamini, 52, died on Sunday afternoon in hospital in South Africa.
 
No cause of death was mentioned, but Dlamini had recently been receiving treatment for coronavirus in South Africa.
 
Dlamini had been Prime Minister of Eswatini, formerly known as Swaziland, since October 2018.
 
The tiny landlocked country in southern Africa is one of the last absolute monarchies in the world.
 
With a population of around one million, the country has recorded 6,768 coronavirus cases and 127 deaths so far, according to the health ministry.
 
Dlamini announced he had tested positive for coronavirus on 16 November. At the time, he said he was asymptomatic and was feeling alright.
 
A few weeks later, on 1 December, the Eswatini government said Dlamini had been moved to a hospital in South Africa, with the aim of fast-tracking his recovery.

But on Sunday the government said Dlamini died "while under medical care in a hospital in South Africa", without giving more details.