President Hage Geingob, aged 82, passed away in hospital early on Sunday, according to a statement issued by Acting President Nangolo Mbumba, weeks after he was diagnosed with cancer.
Geingob died at Lady Pohamba Hospital in Windhoek, where he was receiving treatment from his medical team, the presidency said.
He had returned from a trip to the United States, where he had undergone a two-day treatment as part of a medical trial, according to his office.
Geingob had served as President since 2015 and was currently in his second term.
He also held the position of the country’s first prime minister.