The governing body's appeals committee also rejected former FIFA vice president Reynald Temarii's appeal against a one-year ban for breaking confidentiality rules.
FIFA's appeals panel partially allowed appeals by three former executive committee members - Slim Aloulou, Amadou Diakite and Ahongalu Fusimalohi - who had their bans from all soccer duty for corruption reduced by one year.
The appeal committee announced verdicts after hearing all five cases at FIFA headquarters on Wednesday and Thursday. All the verdicts can be challenged at the Court of Arbitration for Sport.
Temarii's lawyer Geraldine Lesieur said he would file an appeal at the CAS.
Adamu, a former Nigerian government sports minister, is the most senior FIFA official sanctioned for bribery. The appeals body confirmed a FIFA ethics committee ruling that Adamu sought payments from British undercover reporters who posed as lobbyists.
The Sunday Times published edited video in October showing Adamu asking for $800,000 paid directly to him to build four soccer fields in his native Nigeria. He said this could influence how he voted in the Dec. 2 elections.
Temarii was secretly filmed appearing to suggest he could receive $2.3 million to fund a soccer academy in Auckland, New Zealand. However, FIFA's ethics court cleared him of acting corruptly though suspended the Tahitian official for breaking confidentiality and loyalty rules by speaking to the reporters.
The revelations in October rocked FIFA and the World Cup bidding process less than two months before the hosts were chosen.
After Adamu, 58, and Temarii, 43 were suspended by FIFA's ethics court in November, a 22-man executive committee chose Russia to host the 2018 World Cup and Qatar in 2022.
Three former members of FIFA's high command were suspended after advising the reporters how to bribe FIFA officials and to pay $1 million.
Aloulou, a Tunisian lawyer, was one of the most senior figures in FIFA legal structure. He chaired the disputes resolution panel. The ruling Friday means he must serve a one-year ban instead of two.
FIFA referees committee member Diakite, of Mali, and Fusimalohi, chief executive of the Tonga federation, were each initially suspended for three years but will serve two.
A sixth official, Ismail Bhamjee of Botswana, did not appeal his four-year ban. Bhamjee lost his place on the executive body after a ticket scalping scandal at the 2006 World Cup. He was replaced by Adamu.
Adamu's exile from soccer was confirmed Friday, three weeks before he hoped to have his FIFA seat renewed for four more years. He was a provisional candidate in a Confederation for African Football poll scheduled Feb. 23 in Khartoum, Sudan.
Temarii was replaced last month as a FIFA vice president and Oceania confederation president by his former deputy, David Chung of Papua New Guinea.
The appeals body upheld fines of $10,600 for Adamu and $5,300 for Temarii.
The two-day hearings were chaired by Bermuda Football Association President Larry Mussenden, a former attorney general.