Buhari made his feelings known in a statement by his Senior Special Assistant on Media and Publicity, Malam Garba Shehu, in Abuja.
The president described the minister as a strong pillar of his administration.
He commended him for working tirelessly to stem the spread of Coronavirus in the country as a member of the Presidential Task Force on COVID-19.
Buhari also lauded Onyeama for ensuring the safety of Nigerians abroad.
“The country is eternally grateful to Geoffrey Onyeama for his diligence in attracting international support for Nigeria to defeat the Coronavirus pandemic, and boost the economy.
“I wish him speedy recovery,” he said.
Onyeama had earlier on Sunday disclosed, via his Twitter handle, that he tested positive for the Coronavirus and has gone on self isolation.
He said: “Did my fourth COVID-19 test yesterday at the first sign of a throat irritation and unfortunately, this time, it came back positive.
“That is life! Win some, loose some. Heading for isolation in a health facility and praying for the best.”